Used Metal Cutting for sale (41,008)

Condition: new, Year of construction: 2024, This laser metal cutting machine can operate sheet material and pipes. Wattsan 1530 Rotatory can cut stainless steel, carbon steel, galvanized steel, copper, aluminum, and titanium. It also features a protective cabin. The standard equipment set includes a 6-meter-long pipe-cutting module. We may increase the module's size to 12 meters based on your specifications. The cabin protects the operator from reflected radiation and sparks during cutting. You can give our managers a call for additional details! Wattsan 1530 Rotatory Cabin characteristics Working area: 1500x3000 mm Coderzacbopfx Agcerk Laser power: up to 6000 W Virmer provides not only prime machines but also service and delivery. Our engineers and managers are ready to answer all of your questions and provide video assistance if required. Also, owners of Wattsan equipment get lifetime online support. Virmer is located in the Netherlands and works all over Europe. Virmer is Wattsan's official supplier. We provide not only laser engravers, but also metal cutters, welders, markers and cleaning machines. Wattsan is a Chinese manufacturer, which has been creating laser equipment for almost 15 years and keeps evolving with the help of its clients. Thanks to feedback Wattsan made over 50 modernizations, which made machines more reliable, precise and powerful so you could upgrade your business up to the new level. YOU CAN WRITE OR CALL US! WE WILL SELECT THE RIGHT MACHINE FOR YOUR TASK On our company you can find a wide range of machines and components: Laser Metal Cutting Machine; Laser Metal Machine, Fiber Metal Laser, Fiber Metal Laser Engraver; CNC laser machine for metal; Laser machine for wood; CNC laser machine; Laser engraving machine; Laser engraver; Laser cutting machine for plywood; Laser engraver; Laser cutting machine for metal; CNC milling machine; laser marker. Lenses; Chillers; Cooling system for machine; Chiller S&A ; IPG laser, MAX photonics, Raycus; Compressor; Rotary device; Mirror for laser machine.

Condition: new, functionality: fully functional, Year of construction: 2025, Laser source - MAX Photonics Csdpownqbzsfx Agcjrk Table size - 4000x2000mm Control system - FSCUT 6000 Software - Cypnest+Cypcut Laser head - Boci BLT442 Nitrogen proportional valve - SMC Power stabilizer - 120kVA Water cooler - Hanli Load capacity up to 3200kg Laser power - 12000 W X/Y positioning accuracy - ±0.05 mm/m X/Y repeat positioning accuracy - ±0.03 mm/m Maximum travel speed - 120 m/min Maximum acceleration - 1.5 G CNC control - FSCUT 6000 EtherCAT-BUS Power supply - 380V 50Hz three-phase

Condition: new, Year of construction: 2024, 5 Axes FSCUT 3000S CNC Control System DELTA Servo Driver & Motor System Hiwin Guide Liner SMG / KH Rack Raytools / BLT Series Cutting Head HanLi Chiller SMC Proportional Valve. Dairuike Auto Pneumatic Clamp φ220mm Various Diameter Wheels Pneumatic Support Loading Assist System Codpfx Aonr Hghogcjrk Gross weight around 5.5ton

Year of construction: 2006, condition: ready for operation (used), FASTEMS Crodeguk E Tspfx Agcjk Type: MLS-XHD Load max pr. pallet 6.000 kg Machine capacity 5 pcs Pallet capacity 25 pcs Available pallets 19 pcs Loading stations 2 pcs X 2650 mm max Y 2300 mm max Robot with grinding function 1 pcs Layout dimensions 15 x 54 meter Build year 2006

Year of construction: 1970, condition: used, Metal circular saw KKS 350 Blade diameter 350 mm Csdpfohrzahsx Agcsrk

Condition: new, Year of construction: 2025, All-round fiber laser metal tube cutting machine Multiple function options help the laser tube cutting machine be used in numerous tube cutting processes. The slender nozzle allows the laser tuber cutter to avoid interference and cut various types of tubes, including special-shaped tubes like H-Beam, P-Beam, I-beam, etc. Cutting machine clamping becomes convenient, easy and fast, with 3 seconds at the soonest to clamp and high repeat precision Cutting performance and efficiency are improved by maintaining gas flow steady with little turbulence. BodorGenius, combined with the lightning-quick piercing process, completes the whole piercing during it moves down on Z-axis. Thanks to the technology, no reworking is necessary for medium and thick sheet piercing. Angle steel and channel steel cutting are standard with no need fior additional installation. Optimized edge searching method and algorithm guarantee higher cutting precision and better steadiness of the laser cutter. Condition: New Laser Type: Fiber Laser Laser Power: 1500W, 2000W, 3000W, 6000W Maximum machinable tube length: 6500mm/9200mm Chuck drive types: NC electric chuck Graphic Format Supported: AI, BMP, Dst, Dwg, DXF, DXP, LAS, PLT CNC or Not: Yes Crjdpfxehwrhms Agcjk Cooling Mode: WATER COOLING

Year of construction: 2024, condition: new, It's time to enhance your production efficiency by 1.5 times! The Wattsan 1530 Tablechange laser metal cutter can operate materials as thick as 15 mm. It can handle stainless steel, carbon steel, galvanized steel, copper, aluminium, and titanium. This CNC laser cutter for metal has two working tables that measure 1500x3000 mm, which can replace each other. The loading rollers of the accurate Wattsan 1530 facilitate material input. Overall, it improves manufacturing efficiency by eliminating the need to waste time loading and uploading items. You can give our managers a call for additional details! Wattsan 1530 Tablechange characteristics Working area: 1500x3000 mm Laser power: up to 6000 W Weight: 3600 kg Virmer provides not only prime machines but also service and delivery. Our engineers and managers are ready to answer all of your questions and provide video assistance if required. Also, owners of Wattsan equipment get lifetime online support. Virmer is located in the Netherlands and works all over Europe. Virmer is Wattsan's official supplier. We provide not only laser engravers, but also metal cutters, welders, markers and cleaning machines. Wattsan is a Chinese manufacturer, which has been creating laser equipment for almost 15 years and keeps evolving with the help of its clients. Thanks to feedback Wattsan made over 50 modernizations, which made machines more reliable, precise and powerful so you could upgrade your business up to the new level. Crjdpfxeiicv Se Agcok YOU CAN WRITE OR CALL US! WE WILL SELECT THE RIGHT MACHINE FOR YOUR TASK On our company you can find a wide range of machines and components: Laser Metal Cutting Machine; Laser Metal Machine, Fiber Metal Laser, Fiber Metal Laser Engraver; CNC laser machine for metal; Laser machine for wood; CNC laser machine; Laser engraving machine; Laser engraver; Laser cutting machine for plywood; Laser engraver; Laser cutting machine for metal; CNC milling machine; laser marker. Lenses; Chillers; Cooling system for machine; Chiller S&A ; IPG laser, MAX photonics, Raycus; Compressor; Rotary device; Mirror for laser machine.

Condition: new, functionality: fully functional, Laser source: MAX Photonics G5 Laser head: Boci BLT4 autofocus head Control system: FSCUT 9100 Software: Cypnest+Cypcut Table size: 8200 x 3200 mm Load capacity up to 9600 kg Straight cutting area: 8850 x 3700 mm Bevel cutting area: 8100 x 3050 mm Cjdewtzu Aspfx Agcork

Condition: new, FSCUT Ethercat CNC Control System DELTA Ethercat Servo Driver & Motor System Hiwin Guide Liner SMG / KH Rack Raytools / BLT Series Cutting Head Codpfxonr Hcws Agcork Laser source 6kW HanLi Chiller Gross weight around 9.5ton Optional: bevel cutting for sheet

Condition: new, Year of construction: 2025, High-strength welding bed Csdpfx Aow A Ik Njgcjrk Partitioned smoke extraction system Fully automatic butter injection system Cutting area 6000 × 1500 mm X‑axis travel 1520 mm Y‑axis travel 6020 mm Z‑axis travel 80 mm Max. combined positioning speed 170 m/min Acceleration 2.8 G Machine dimensions (L × W × H) 14500 × 2300 × 2380 mm Floor footprint 15500 × 2800 mm Net weight 6000 kg Fully automatic cutting, material saving, fast speed

Condition: new, Bernardo manual metal circular saw CS 315 H Technical specifications Saw blade diameter of 315 x 40 mm Speed 19 / 38 U/min Vice opened Max 150 mm Working height 920 mm S1 motor power output 100% 0,75 / 1,5 kW Motor power S6 40% 1.0 / 2,1 kW Credod Id Ugepfx Agcjk Voltage 400 V Machine dimensions (W x D x H) 530 x 1000 x 1740 mm Weight 235 kg Round solid material 90°: 80 mm 45°: 70 mm Round tube 90°: 80 mm 45°: 70 mm Square shaped tube 90°: 80 x 80 mm 45: 70 x 70 mm Solid material square 90°: 80 x 80 mm 45: 70 x 70 mm Square tube rectangular 90°: 90 x 80 mm 45: 80 x 70 mm Rectangular solid material 90°: 90 x 80 mm 45: 80 x 70 mm Properties Gear head for slot working left and right 90 ° swiveling Removable coolant tank in the robust base integriergt Gearbox with hardened and ground Auger and bronze worm wheel Security guard opens automatically when the cutting Precise, 4 guided, self-centering double clamping vise Ergonomically shaped handle with push button for fatigue-free cutting Low speed of the saw blade (19 / 38 RPM) optimal for cutting of full materials Reduction gear low noise running in an oil bath Scope of delivery Coolant system with filter Self centering Vice Base

Condition: new, Year of construction: 2025, All-round fiber laser metal tube cutting machine Multiple function options help the laser tube cutting machine be used in numerous tube cutting processes. The slender nozzle allows the laser tuber cutter to avoid interference and cut various types of tubes, including special-shaped tubes like H-Beam, P-Beam, I-beam, etc. Cutting machine clamping becomes convenient, easy and fast, with 3 seconds at the soonest to clamp and high repeat precision Cutting performance and efficiency are improved by maintaining gas flow steady with little turbulence. BodorGenius, combined with the lightning-quick piercing process, completes the whole piercing during it moves down on Z-axis. Thanks to the technology, no reworking is necessary for medium and thick sheet piercing. Angle steel and channel steel cutting are standard with no need for additional installation. Optimized edge searching method and algorithm guarantee higher cutting precision and better steadiness of the laser cutter. Condition: New Codshwrk Topfx Agcork Laser Type: Fiber Laser Laser Power: 1500W, 2000W, 3000W, 6000W Maximum machinable tube length: 6500mm/9200mm Chuck drive types: NC electric chuck Graphic Format Supported: AI, BMP, Dst, Dwg, DXF, DXP, LAS, PLT CNC or Not: Yes Cooling Mode: WATER COOLING

Year of construction: 2024, condition: new, This laser metal cutting machine can operate sheet material with a thickness up to 12 mm. Wattsan 1235 can cut stainless steel, carbon steel, galvanized steel, copper, aluminum, and titanium. It features a working space of 1300x2500 mm. The loading rollers of the precise Wattsan 1325 S make material feeding easier. The S-series laser metal machine has a maximum travel speed of 120 meters per minute. Laser power can be up to 6 kw. The bed here is made of steel. You can give our managers a call for additional details! Wattsan characteristics Working area: 1300x2500 mm Cjdpfx Agoiicwzecsrk Laser power: up to 6000 W Weight: 1640 Virmer provides not only prime machines but also service and delivery. Our engineers and managers are ready to answer all of your questions and provide video assistance if required. Also, owners of Wattsan equipment get lifetime online support. Virmer is located in the Netherlands and works all over Europe. Virmer is Wattsan's official supplier. We provide not only laser engravers, but also metal cutters, welders, markers and cleaning machines. Wattsan is a Chinese manufacturer, which has been creating laser equipment for almost 15 years and keeps evolving with the help of its clients. Thanks to feedback Wattsan made over 50 modernizations, which made machines more reliable, precise and powerful so you could upgrade your business up to the new level. YOU CAN WRITE OR CALL US! WE WILL SELECT THE RIGHT MACHINE FOR YOUR TASK On our company you can find a wide range of machines and components: Laser Metal Cutting Machine; Laser Metal Machine, Fiber Metal Laser, Fiber Metal Laser Engraver; CNC laser machine for metal; Laser machine for wood; CNC laser machine; Laser engraving machine; Laser engraver; Laser cutting machine for plywood; Laser engraver; Laser cutting machine for metal; CNC milling machine; laser marker. Lenses; Chillers; Cooling system for machine; Chiller S&A ; IPG laser, MAX photonics, Raycus; Compressor; Rotary device; Mirror for laser machine.

Condition: new, Year of construction: 2024, Laser source: 12 kW Raycus/IPG Laser head: Precitec Pro-Cutter 2.0 Control system: FSCUT 8000 Effective working area: 1520x3050 mm Max. Positioning speed: 120 m/min Max. Acceleration: 1,5 m/s² Positioning accuracy: 0,02 mm/m Csdpfx Agji Ar Ruecjrk Repeatability: 0.03 mm/m Max. Table load: 1500 kg

Condition: new, Year of construction: 2025, sheet thickness steel (max.): 4 mm, back gauge: 1,000 mm, CIDAN EVO DUO metal shear is the strongest mechanical shear on the market, with a capacity to handle sheet thicknesses from 0.5 mm to 4.0 mm in the same machine (applies to EVO DUO 32). EVO DUO is a powerful built guillotine shear equipped with two (DUO) gearmotors that distribute power and load optimally. The CIDAN EVO DUO metal shear is available in two lengths, 3200 mm and 4100 mm. The machine is well equipped as standard with a lot of features that creates a perfect working environment that meets the greatest demands on efficiency and ergonomics: Crsdsm Nbq Rjpfx Agcsk Blade gap adjustment Sheet support – supports the material during the cut, as standard designed for return to sender. As option with delivery to the rear side of the machine. Pneumatic hold-down beam that enables gentle handling of softer materials, such as aluminum. The distance from the hold-down beam to the cutting line is less than 35 mm, which minimizes the material waste. Flexible table with T-groove rails for table pans, fixed and adjustable angular stops and support arms that can be rearranged and replaced. EVO DUO guillotine shear can be equipped with a 750 or 1000 mm programmable back gauge with CutLink finger touch control. The back gauge is a fast and accurate positioning system with many interesting functions that facilitate the handling of the sheet metal. CIDAN shear EVO DUO fits well with the CIDAN philosophy of low environmental impact, as the machine has low energy consumption, a very low noise level and is designed for maximum usability.

Condition: new, functionality: fully functional, power: 3 kW (4.08 HP), Year of construction: 2025, Equipment: air conditioning, cooling unit, G16 Credpfxowz Ufwj Agcok Type: Two chucks

Condition: used, Metal cutting sheet up to 2000 mm wide Metal sheet thickness up to 12 mm Credpfx Agsri Ncnocsk Ease of control, cutting accuracy and good performance are the main advantages of the HA 3121 guillotine.

Condition: new, Year of construction: 2025, All-round fiber laser metal tube cutting machine Multiple function options help the laser tube cutting machine be used in numerous tube cutting processes. The slender nozzle allows the laser tuber cutter to avoid interference and cut various types of tubes, including special-shaped tubes like H-Beam, P-Beam, I-beam, etc. Cutting machine clamping becomes convenient, easy and fast, with 3 seconds at the soonest to clamp and high repeat precision Cutting performance and efficiency are improved by maintaining gas flow steady with little turbulence. BodorGenius, combined with the lightning-quick piercing process, completes the whole piercing during it moves down on Z-axis. Thanks to the technology, no reworking is necessary for medium and thick sheet piercing. Angle steel and channel steel cutting are standard with no need fior additional installation. Optimized edge searching method and algorithm guarantee higher cutting precision and better steadiness of the laser cutter. Condition: New Laser Type: Fiber Laser Laser Power: 1500W, 2000W, 3000W, 6000W Maximum machinable tube length: 6500mm/9200mm Chuck drive types: NC electric chuck Graphic Format Supported: AI, BMP, Dst, Dwg, DXF, DXP, LAS, PLT CNC or Not: Yes Cooling Mode: WATER COOLING Cjdjhwrhfjpfx Agcerk

Condition: new, Year of construction: 2024, This laser metal cutting machine can operate sheet material with a thickness up to 12 mm. Wattsan 1530 can cut stainless steel, carbon steel, galvanized steel, copper, aluminum, and titanium. It features a working space of 1500x3000 mm. The loading rollers of the precise Wattsan 1530 S make material feeding easier. The S-series laser metal machine has a maximum travel speed of 120 meters per minute. Laser power can be up to 6 kw. The bed here is made of steel. You can give our managers a call for additional details! Wattsan 1530 S characteristics Working area: 1500x3000 mm Laser power: up to 6000 W Weight: 2640 kg Virmer provides not only prime machines but also service and delivery. Our engineers and managers are ready to answer all of your questions and provide video assistance if required. Also, owners of Wattsan equipment get lifetime online support. Virmer is located in the Netherlands and works all over Europe. Virmer is Wattsan's official supplier. We provide not only laser engravers, but also metal cutters, welders, markers and cleaning machines. Wattsan is a Chinese manufacturer, which has been creating laser equipment for almost 15 years and keeps evolving with the help of its clients. Thanks to feedback Wattsan made over 50 modernizations, which made machines more reliable, precise and powerful so you could upgrade your business up to the new level. YOU CAN WRITE OR CALL US! WE WILL SELECT THE RIGHT MACHINE FOR YOUR TASK On our company you can find a wide range of machines and components: Laser Metal Cutting Machine; Laser Metal Machine, Fiber Metal Laser, Fiber Metal Laser Engraver; CNC laser machine for metal; Laser machine for wood; CNC laser machine; Laser engraving machine; Laser engraver; Laser cutting machine for plywood; Laser engraver; Laser cutting machine for metal; CNC milling machine; laser marker. Lenses; Chillers; Cooling system for machine; Chiller S&A ; IPG laser, MAX photonics, Raycus; Compressor; Rotary device; Mirror for laser machine. Cjdpfx Agery U Iyocjrk

Condition: as good as new (ex-display), Hans Schreiner metal band saw - exhibition machine! Technical data: Motor output S6 1900 W (1500 W S6-100%Ed, roller diameter 380 mm, saw blade dimensions 3160 x 27 x 0.9 mm, swivel range 45° left, 60° right, cutting range at 90° max. 370 x 220 mm, cutting speed 34 / 68 m/min, packaging dimensions L x W x H 1770 x 765 x 1120 mm, weight 365 kg Symbolic photo Codpovrvu Aofx Agcerk Prices subject to change, errors, printing and typesetting errors reserved

Condition: new, functionality: fully functional, Year of construction: 2025, Equipment: CE marking, centralized greasing system, cooling unit, documentation/manual, dust extraction, emergency stop, fume extraction, nozzle changer, safety light barrier, Series: GS-CEW Type: Exchange table, full protection, full protection exchange table Laser power: 3KW, 6KW.12KW, 15KW, 20KW Standard hardware: Scrap car, fully automatic butter injection, dual-control workbench, adaptive multi-angle site placement, rear lift light-blocking door, beam light curtain, partition dust removal Optional hardware: Fire bricks, high-pressure proportional valve (standard above 6KW), safety door lock, independent laser cabinet, rear exchange table light curtain, rear camera, internal camera, monitoring display, radiation-proof glass, upper cover fan, upper cover, light-blocking rubber strip Credpfewxar Dsx Agcsk Optional functions: FDA configuration CSA configuration, TUV configuration conventional CE configuration

Condition: new, Year of construction: 2025, All-round fiber laser metal tube cutting machine Multiple function options help the laser tube cutting machine be used in numerous tube cutting processes. The slender nozzle allows the laser tuber cutter to avoid interference and cut various types of tubes, including special-shaped tubes like H-Beam, P-Beam, I-beam, etc. Cutting machine clamping becomes convenient, easy and fast, with 3 seconds at the soonest to clamp and high repeat precision Cutting performance and efficiency are improved by maintaining gas flow steady with little turbulence. BodorGenius, combined with the lightning-quick piercing process, completes the whole piercing during it moves down on Z-axis. Thanks to the technology, no reworking is necessary for medium and thick sheet piercing. Angle steel and channel steel cutting are standard with no need for additional installation. Optimized edge searching method and algorithm guarantee higher cutting precision and better steadiness of the laser cutter. Crodpfxshwri Sj Agcek Condition: New Laser Type: Fiber Laser Laser Power: 1500W, 2000W, 3000W, 6000W Maximum machinable tube length: 6500mm/9200mm Chuck drive types: NC electric chuck Graphic Format Supported: AI, BMP, Dst, Dwg, DXF, DXP, LAS, PLT CNC or Not: Yes Cooling Mode: WATER COOLING

Year of construction: 2024, condition: new, This laser metal cutting machine can operate sheet material with a thickness of 3-4 mm. Wattsan 1325 can cut stainless steel, carbon steel, galvanized steel, copper, aluminum, and titanium. It features a working space of 1300x2500 mm. The loading rollers of the precise Wattsan 13250 E make material feeding easier. The E-series laser metal machine has a maximum travel speed of 80 meters per minute. Laser power can be up to 1,5 kw. The bed here is made of steel. You can give our managers a call for additional details! Wattsan 1325 E characteristics Working area: 1300x2500 mm Laser power: up to 1500 W Weight: 1620 kg Virmer provides not only prime machines but also service and delivery. Our engineers and managers are ready to answer all of your questions and provide video assistance if required. Also, owners of Wattsan equipment get lifetime online support. Virmer is located in the Netherlands and works all over Europe. Virmer is Wattsan's official supplier. We provide not only laser engravers, but also metal cutters, welders, markers and cleaning machines. Credpfeiicw Ejx Agcjk Wattsan is a Chinese manufacturer, which has been creating laser equipment for almost 15 years and keeps evolving with the help of its clients. Thanks to feedback Wattsan made over 50 modernizations, which made machines more reliable, precise and powerful so you could upgrade your business up to the new level. YOU CAN WRITE OR CALL US! WE WILL SELECT THE RIGHT MACHINE FOR YOUR TASK On our company you can find a wide range of machines and components: Laser Metal Cutting Machine; Laser Metal Machine, Fiber Metal Laser, Fiber Metal Laser Engraver; CNC laser machine for metal; Laser machine for wood; CNC laser machine; Laser engraving machine; Laser engraver; Laser cutting machine for plywood; Laser engraver; Laser cutting machine for metal; CNC milling machine; laser marker. Lenses; Chillers; Cooling system for machine; Chiller S&A ; IPG laser, MAX photonics, Raycus; Compressor; Rotary device; Mirror for laser machine.

Condition: new, Hans Schreiner metal bandsaw with pivoting cutter arm, for the professional, with soft hydraulic for the correct pressure, electrical coolant system for all kind of metals, steels and Nirosta, quick clamping vice automatic cut stop, the semi-automatic control with preprogrammed cycle (user starts - clamping workpiece - cutting - saw arm resetting - unclamp workpiece) is optional at the MBS370SA for metal worker and workshops with small - and mass serial products. Strengthened frame for more stability. CE conform Motor: 400V,50Hz Reduce gear rate: 25:1 Crjdpsvrv Dqofx Agcsk Wheel diameter: 380mm Blade size: 3160x27x0.9mm Blade speed: 34 or 68 m/min Cutting angle: 45°L, 30°L, 15°L, 0°, 15°R, 30°R, 45°R, 60°R Coolant pump: 400V, 50Hz, 3~, 25W Packing size: 1770x765x1120mm Weight: 365 kg

Condition: new, functionality: fully functional, Year of construction: 2025, laser power: 30,000 W, travel distance X-axis: 3,050 mm, travel distance Y-axis: 13,050 mm, travel distance Z-axis: 450 mm, positioning accuracy: 0.03 mm, repeat accuracy: 0.02 mm, workpiece weight (max.): 2,000 kg, input voltage: 380 V, input frequency: 50 Hz, total length: 16,800 mm, total width: 2,200 mm, total height: 5,120 mm, warranty duration: 24 months, working range: 13,000 mm, Equipment: cooling unit, All New Full Cover Fiber Laser Cutting Machine | GS-CE PRO Series | 6000-40000W MACHINE AVAILABLE ON HAND This GS-CE series FULL COVER FIBER LASER CUTTING MACHINE offers maximum safety for metals cutting. Thanks to its full cover structure and protective glass observation window, you can observe the operation and avoid hazards such as laser radiation, sparks, etc. It also has a fast exchange table, and the exchange is within 10s. It will be your ideal solution for safe and efficient metal cutting! Working platform size: 4000mm*2000mm Laser power 6KW-40KW Codpjv Hnl Ajfx Agcerk GS-4020CE PRO Intelligent anti-collision function Automatic lubrication Laser fault alarm Cooling fault alarm Laser protection glass Water cooler TÜV CE certificate Optional function: automatic loading and unloading system Control unit supports graphic formats: AI, BMP, Dst, Dwg, DXF, DXP External programming System complete incl. cooler, extraction system and safety light barriers