Used Okuma Mb 56 Va for sale (206)

Condition: good (used), Year of construction: 2002, functionality: fully functional, Equipment: chip conveyor, documentation/manual, rotational speed infinitely variable, Okuma MB56VA 3-axis vertical machining center U100M ATC 32 SK40 Lhjdpfxsyiu D Is Ab Toc Main spindle 12,000 rpm Oil mist extraction system Cutting time 9,675 h Chip conveyor Coolant system *optionally, a large selection of SK40 tools matching the machine

Condition: good (used), Year of construction: 2006, 3-axis machining center Okuma MB-66 VA Control: OSP-P 200M Year of manufacture: 2006 Lhjdpfxoylwp Ss Ab Tjc X-axis: 1,500 mm Y-axis: 660 mm Z-axis: 660 mm Tool holder: SK 40 MASBT Tool magazine: 32 stations Spindle speed: 8,000 rpm Equipment: ONE touch IGF Hinged belt conveyor Electronic handwheel Internal coolant supply 20 bar

Condition: ready for operation (used), Year of construction: 2003, functionality: fully functional, machine/vehicle number: 107963, travel distance X-axis: 1,050 mm, travel distance Y-axis: 560 mm, travel distance Z-axis: 460 mm, controller model: OSP U100, spindle speed (max.): 15,000 rpm, TECHNICAL DETAILS X-axis travel: 1,050 mm Y-axis travel: 560 mm Z-axis travel: 460 mm Table Max. workpiece dimensions: 1,300 x 560 mm Distance from table surface to spindle nose: 150 – 610 mm Max. table load: 900 kg Spindle Spindle speed: 15,000 rpm Spindle power: 22 / 18.5 kW Cooling through spindle: 20 bar Lsdpfxewh Tfvj Ab Tshc Feed rates Rapid traverse X/Y-axis: 40 m/min Rapid traverse Z-axis: 32 m/min Working feed X/Y/Z-axis: 32 m/min Tool magazine Tool capacity: 20 tools Tool holder: BT 40 Tool selection: Memory Random MACHINE DETAILS Footprint: 2,510 x 3,100 mm Machine height: 2,476 mm Machine weight: 7,500 kg EQUIPMENT - Chip conveyor

Condition: good (used), Year of construction: 2005, Vertical Machining Center Okuma MB 46-VAE Control: OSP-E100M Year of manufacture: 2005 Travel Paths: X-axis: 600 mm Y-axis: 460 mm Z-axis: 460 mm Lhedpfxjylwdcj Ab Tjc Max. workpiece weight: 500 kg Clamping area: 1,000 x 460 mm Spindle taper: SK 40 DIN ISO 69871 Tool magazine: 32 stations Spindle speed: max. 15,000 rpm Equipment - ICS / Internal coolant supply - Chip conveyor - USB drive

Condition: ready for operation (used), Year of construction: 2007, functionality: fully functional, travel distance X-axis: 762 mm, travel distance Y-axis: 460 mm, travel distance Z-axis: 460 mm, controller model: OSP-P200M, rotational speed (max.): 15,000 rpm, TECHNICAL DETAILS Travel X-axis: 762 mm Travel Y-axis: 460 mm Travel Z-axis: 460 mm Spindle speed range: 50 - 15,000 rpm Rapid traverse X-axis: 40 m/min Rapid traverse Y-axis: 40 m/min Rapid traverse Z-axis: 32 m/min Tool magazine: 32 positions MACHINE DETAILS Control: OSP-P200M Main drive motor: 22 kW Dimensions & Weight Required space (L x W x H): 2,850 x 2,810 x 2,750 mm Machine weight: 7,200 kg EQUIPMENT Chip conveyor Lhsdpfxjx I Ecye Ab Tjc Internal coolant supply Standard filtration unit

Condition: ready for operation (used), Year of construction: 2005, General Data Machine weight 6900 kg Measurements height 2750 mm Measurements depth 3000 mm Dimensions Machine Length 2550 mm Main Drive Ljdpfx Aex D Dvbjb Tehc Number of axis 3 Movement X-Axis Movement 1050 mm Z-Axis Movement 460 mm Y-Axis Movement 560 mm This 3-axis Okuma MB-56VB vertical machining center was manufactured in 2005. It features a working surface of 1300 × 560 mm, a maximum table load of 900 kg, and rapid feed rates of 40 m/min in X/Y and 32 m/min in Z. The spindle operates up to 12,000 rpm with a power of 20 kW. Tool magazine holds 32 tools. If you are looking to get high-quality milling capabilities consider the Okuma MB-56VB machine we have for sale. Contact us for more information. Application Types Milling

Condition: ready for operation (used), Year of construction: 2007, functionality: fully functional, travel distance X-axis: 762 mm, travel distance Y-axis: 460 mm, travel distance Z-axis: 460 mm, number of slots in tool magazine: 32, controller model: OSP-P200M, spindle speed (max.): 15,000 rpm, TECHNICAL DETAILS X-travel: 762 mm Y-travel: 460 mm Z-travel: 460 mm Control: OSP-P200M Tool magazine: 32 tools X-axis rapid traverse: 40 m/min Y-axis rapid traverse: 40 m/min Z-axis rapid traverse: 32 m/min Ledpfx Ajv Umt Ujb Tohc Speed range: 50 – 15,000 rpm Main drive motor: 22 kW MACHINE DETAILS Machine dimensions: approx. 2,850 × 2,810 × 2,750 mm Machine weight: approx. 7,200 kg EQUIPMENT - Chip conveyor - Internal coolant supply - Standard filter system

Condition: excellent (used), Year of construction: 2007, Okuma MB-46VAE Machining Center Year of manufacture: 2007 Control: OKUMA OSP P200-M Table size: 1000 x 460 mm X travel: 762 mm Lodsxwtp Djpfx Ab Tjhc Y travel: 460 mm Z travel: 460 mm Table load capacity: 700 kg Spindle cooler Taper: MAS BT40 Magazine with 42 tool stations Weight: 6500 kg Dimensions LxWxH = 2750 x 2160 x 2715 mm

Condition: excellent (used), Year of construction: 2008, functionality: fully functional, Controller OKUMA OSP P200-M Table size 1000 x 460 mm Table load 700 kgs X travel 762 mm Y travel 460 mm Z travel 460 mm Spindle speed 15000 rpm Tool holder type MAS BT40 ATC magazin 20-fold Weight 6500 kgs Dimensions LxWxH = 2750 x 2160 x 2715 mm Features, accessories - Chip conveyor - Coolant unit - Spindle cooler Ljdpfx Absuu Rwys Tehc - CTS - Manuals Very good condition.It will be sold because of liquidation of production.

Condition: used, Year of construction: 2005, For sale: CNC Machining Center OKUMA ACE CENTER MD-56VA (2005) Condition: Good, fully functional. Manufacturer: OKUMA Corporation (Japan) Model: ACE CENTER MD-56VA Year of manufacture: 2005 Lsdpfxjxp Utbs Ab Tshc Reliable vertical CNC machining center designed for precise milling, drilling, and tapping of metal components. OKUMA is one of the most renowned Japanese manufacturers, known for the precision and durability of its machine tools. Main technical specifications (according to MD-56VA model): Control: OKUMA OSP-E100M Travel: X = 1050 mm / Y = 560 mm / Z = 460 mm Table size: 1300 × 560 mm Max. table load: 800 kg Spindle speed: up to 15,000 rpm Spindle taper: BT40 Tool changer: 20 positions (automatic) Spindle motor: 15/11 kW (continuous/rated power) Power supply: 400 V / 50 Hz Cooling system: integrated Approx. weight: 7,000 kg Application: The OKUMA MD-56VA CNC machining center is designed for high-precision metal parts production: - Mechanical components - Molds and tools - Machining of aluminum, steel, and non-ferrous metals Ideally suited for precision manufacturing and small to medium series where accuracy and repeatability are crucial. If you have any further questions, please feel free to contact us.

Condition: used, Year of construction: 2014, Technical details: x-travel: 760 mm y-travel: 760 mm z-travel: 760 mm total power requirement: 43 kW weight of the machine ca.: 11,5 t Lhjdpfx Asxrwpdjb Tsc dimensions of the machine ca.: 2,7 x 4,73 x 2,87 m max. table loading capacity: 500 kg

Condition: used, Year of construction: 2002, operating hours: 10,500 h, functionality: fully functional, travel distance X-axis: 762 mm, travel distance Y-axis: 460 mm, travel distance Z-axis: 460 mm, controller manufacturer: Okuma, controller model: U100, spindle speed (max.): 8,000 rpm, coolant supply: 12 bar, Equipment: chip conveyor, documentation/manual, rotational speed infinitely variable, Okuma MB46 from 2002 Low operating hours! Machine can be inspected under power. 32 tools BT40 Scraper belt conveyor Internal cooling 8 bar 8,000 rpm 4th axis included Lsdpfxowt Dqao Ab Tohc

Condition: ready for operation (used), Year of construction: 2011, General Data Measurements width 4710 mm Measurements depth 2700 mm Measurements height 2864 mm Machine weight 11500 kg Main Drive Spindle speed range 50 to 15000 Tool taper SK40 Number of axis 4 Movement X-Axis Movement 760 mm X-Axis Rapid Traverse 60 m/min Y-Axis Movement 760 mm Y-Axis Rapid Traverse 60 m/min Z-Axis Movement 760 mm Z-Axis Rapid Traverse 60 m/min Table Lhodpfjx D Rrijx Ab Tec Table load 500 kg Tools Max weight 10 kg Max tool diameter 70 / 150 mm Max tool length 300–450 mm This 4-axis Okuma MB 5000H was manufactured in 2011. It features a robust horizontal machining center design with a 500 × 500 mm pallet size, capable of handling a maximum load of 500 kg. The spindle supports speeds from 50 to 15,000 min⁻¹ with a SK40 taper, enhancing its versatility. Additional features include a chip conveyor, shower system, and provision for a Renishaw probe. If you are looking to get high-quality milling capabilities consider the Okuma MB 5000H machine we have for sale. Contact us for more information. Application Types Milling

Condition: ready for operation (used), Year of construction: 2010, General Data Measurements height 2864 mm Machine weight 11500 kg Main Drive Spindle speed range 50–15,000 Tool taper SK40 Number of axis 4 Movement X-Axis Movement 760 mm X-Axis Rapid Traverse 60 m/min Y-Axis Movement 760 mm Y-Axis Rapid Traverse 60 m/min Z-Axis Movement 760 mm Z-Axis Rapid Traverse 60 m/min Tools Lhjdpfx Asx D Rrcjb Toc Max weight 10 kg Max tool diameter 70 mm / 150 mm Max tool length 300–450 mm Type of tool holder BT40 This 4-axis Okuma MB 5000H was manufactured in 2010. It features a robust 500 × 500 mm pallet, capable of handling a maximum load of 500 kg, and offers a comprehensive range of movements with 760 mm travel in X, Y, and Z axes. Equipped with a high-speed spindle up to 15,000 min⁻¹ and a 64-tool magazine, this horizontal machining centre is ideal for complex machining tasks. Contact us for more information about this machine. Application Types Milling

Condition: ready for operation (used), Year of construction: 2014, functionality: fully functional, travel distance X-axis: 760 mm, travel distance Y-axis: 760 mm, travel distance Z-axis: 760 mm, table load: 500 kg, spindle speed (max.): 15,000 rpm, TECHNICAL DETAILS X-axis travel: 760 mm Y-axis travel: 760 mm Z-axis travel: 760 mm Spindle center to table surface: 50 to 810 mm Spindle end to table center: 135 to 895 mm Table size: 500 x 500 mm Max. load capacity: 500 kg Index positions: 360 Ledpfexvq Hdsx Ab Tjhc Speed range: 50 to 15,000 rpm Number of speed ranges: stepless Taper: NT No. 40 Spindle diameter: 70 mm Feed Rapid traverse (X/Y/Z): 60,000 mm/min Manual feed (X/Y/Z): 1 to 60,000 mm/min Tool changer Tool holder: Standard MAS BT40 Magazine capacity: 48 stations Max. tool diameter (adjacent positions occupied): 70 mm Max. tool diameter (adjacent positions free): 150 mm Max. tool length: 300 mm Max. tool weight: 10 kg MACHINE DETAILS Total power requirement: 43 kW Dimensions & Weight Space requirement: 2.7 x 4.73 x 2.87 m Machine weight: 11.5 t

Condition: excellent (used), Year of construction: 2001, functionality: fully functional, machine/vehicle number: 1067, travel distance X-axis: 1,050 mm, travel distance Y-axis: 560 mm, travel distance Z-axis: 450 mm, rapid traverse X-axis: 40 m/min, rapid traverse Y-axis: 40 m/min, rapid traverse Z-axis: 40 m/min, nominal power (apparent): 28 kVA, torque: 80 Nm, controller manufacturer: Okuma, controller model: OSP-U100L, workpiece height (max.): 500 mm, workpiece weight (max.): 700 kg, table width: 560 mm, table length: 1,300 mm, spindle speed (min.): 40 rpm, spindle speed (max.): 15,000 rpm, operating hours of spindle: 15,000 h, coolant supply: 20 bar, spindle nose: BT-40, number of slots in tool magazine: 20, input voltage: 400 V, type of input current: AC, Equipment: documentation/manual, rotational speed infinitely variable, 3-axis machining center with internal cooling through the spindle, 15,000 rpm, permanent oil cooling of the spindle. Various tool holders (collets, drill chucks, Weldon holders, and milling head holders). 3 Gressel-Gripos 125 mm vises as new, additionally tool presetting device PWB Toolmaster 250. Lhedpfxsw S Nc Re Ab Toc

Condition: excellent (used), Year of construction: 2011, travel distance X-axis: 560 mm, travel distance Y-axis: 560 mm, travel distance Z-axis: 625 mm, torque: 163 Nm, coolant supply: 20 bar, nominal power (apparent): 30 kVA, number of spindles: 48, rapid traverse Z-axis: 60 m/min, rapid traverse X-axis: 60 m/min, rapid traverse Y-axis: 60 m/min, rotary table diameter: 400 mm, rotational speed (max.): 15,000 rpm, table load: 400 kg, tool diameter: 70 mm, tool length: 300 mm, tool weight: 10 g, Equipment: chip conveyor, documentation/manual, rotational speed infinitely variable, Technical characteristics: CNC OSP P 200 Chip conveyor 48 tools Continuous table 360,000 pos. 15,000 rpm BT 40 Cooling through spindle 20 Bar Presetting on board table Lsdpfx Abjuw Sq Ue Tehc Shower work area washing system P.S. The machine has always worked in full oil Teflon material

Condition: excellent (used), Year of construction: 2007, functionality: fully functional, travel distance X-axis: 1,250 mm, travel distance Y-axis: 660 mm, travel distance Z-axis: 540 mm, rapid traverse X-axis: 40 m/min, rapid traverse Y-axis: 40 m/min, rapid traverse Z-axis: 32 m/min, feed rate X-axis: 32 m/min, feed rate Y-axis: 32 m/min, feed rate Z-axis: 32 m/min, controller manufacturer: Okuma, controller model: OSP P200M-H, rotary table diameter: 500 mm, Equipment: chip conveyor, documentation/manual, rotational speed infinitely variable, Okuma MU500VA CNC Vertical Machining Centre (2007) Equipped with OKUMA OSP P200M-H CNC CONTROL 20" ROTARY PLATEN 4TH AND 5TH AXIS BUILT IN TRUNION 32 POSITION AUTOMATIC TOOL CHANGER COOLANT THRU SPINDLE TOOL LENGTH MEASURING Travels X-axis (saddle left/right) – 1250mm, Y-axis (pallet front/back) – 660mm, Z-axis (spindle up/down) – 540mm, A-axis – +20~-110 deg., C-axis – 360 deg., Table surface to spindle nose – 127~667mm Table Table size – ø500mm, Max work size – ø730xh500, Floor to table top – 1073mm, Max load capacity – 500kg Spindle Spindle speed – 15000rpm, Turning specification – C-axis table 1000rpm , No. of spindle ranges – Infinitely variable, Tapered bore – 7/24 taper No.40, Bearing dia – ø70mm Feed Rapid traverse – X-Y: 40m/min, Z:32m/min, Rapid traverse (A-C) – 18,000 deg/min, Cutting feed rate – X-Y-Z: 32m/min Motors Spindle (10min/cont) – 11/7.5kW ATC Tool shank type – MAS BT40 Big plus, Retention knob type – MAS 2, Tool capacity – 32, Max. tool dia (w/ adjacent tool) – ø90mm, Max. tool dia (w/o adjacent tool) – ø125mm, Max. tool length – 400mm, Max. tool mass – 8kg, Tool selection – Memory random Lodpfxjyf Ncqe Ab Tjhc ATC Retention knob type – MAS 2, Tool capacity – 32, Max. tool dia (w/ adjacent tool) – ø90mm, Max. tool dia (w/o adjacent tool) – ø125mm, Max. tool length – 400mm, Max. tool mass – 8kg, Tool selection – Memory random

Condition: excellent (used), Year of construction: 2007, machine/vehicle number: 126937, functionality: fully functional, travel distance X-axis: 762 mm, travel distance Y-axis: 460 mm, travel distance Z-axis: 460 mm, number of slots in tool magazine: 32, controller manufacturer: Okuma, controller model: P200M-H, rotary table diameter: 400 mm, OKUMA MU-400VA 5-AXIS CNC VERTICAL MACHINING CENTER, FROM AEROSPACE COMPANY, 16" ROTARY PLATEN, 4TH AND 5TH AXIS BUILD IN TRUNION, 15,000 RPM 32 POSITION TOOL CHANGER, OSP P200M-H CNC CONTROL Okuma MU400VA CNC Vertical Machining Centre (2007) Lodou Illaepfx Ab Tjhc Description: Control OSP P200 Table working surface - 15.75", Max table load - 600lbs, X Axis travel - 30", Y Axis travel - 18.11", Z Axis travel - 18.11", A Axis trunnion tilt - +20 to -110deg, B Axis table rotation - 360deg, Table surface to spindle nose - 3.94" - 22.05", Rapids X & Y - 15.75 IPM, Spindle taper - CAT 40, Spindle speeds - 16000 RPM, Spindle Motor - 20HP, Tool magazine capacity - 32 Table Size 15.75" Dia Table Load Capacity 660 LBS # Axis 5 X-Axis (Longitudinal Travel) 30" Y-Axis (Cross Travel) 18.11" Z-Axis (Vertical Travel) 18.11" A-Axis (Trunnion Tilt Range) (±25°) +20° to -110° C-Axis Table Rotation Positioning 360,000° Max/Min Clearance Table Top to Spindle Nose 22.05" / 3.94" Distance Floor to Table Top 41.34" Rapid Traverse Rate (X, Y, & Z Axis) 1,574 IPM Spindle Horsepower 20 HP Max Spindle Speed 15,000 RPM Spindle Taper MAS BT40 Big plus Coolant Thru Spindle yes Automatic Tool Changer Capacity (ATC) 32 Electrics 220/3/60 Approximate Machine Dimensions 114" x 160" Approximate Machine Height 116" Approximate Machine Weight 17,000 LBS OKUMA OSP P200M-H CNC CONTROL BUILT IN 4TH AND 5TH AXIS 16" DIAMETER TRUNION TABLE 15,000 RPM SPINDLE LASER TOOL SETTER 32 POSITION AUTOMATIC TOOL CHANGER COOLANT THRU SPINDLE CHIP CONVEYOR

Condition: ready for operation (used), Year of construction: 1999, travel distance X-axis: 560 mm, travel distance Y-axis: 460 mm, travel distance Z-axis: 450 mm, total height: 2,650 mm, total width: 1,800 mm, overall weight: 5,000 kg, spindle speed (max.): 7,000 rpm, spindle motor power: 11,000 W, tool weight: 8,000 g, number of axes: 3, This 3s Okuma MX-45VAE vertical machining centre was manufactured in 1999. It features a travel range of 560 mm on the X-axis, 460 mm on the Y-axis, and 450 mm on the Z-axis, providing versatile machining capabilities. With a tool magazine capacity of 20 tools and a maximum tool weight of 8 kg, it is well-equipped for various applications. Consider the opportunity to buy this Okuma MX-45VAE vertical machining centre. Contact us for further details. • Spindle end to table surface: 160–610 mm (6.30–24.02 in) • Table: • Working surface: 460 × 760 mm (18.11 × 29.92 in) [optional: 460 × 1000 mm (18.11 × 39.37 in)] • Table surface height from floor: 750 mm (29.53 in) • Load capacity: 3430 N (770 lbf) [optional: 4900 N (1100 lbf)] • Spindle: • Number of speeds: Infinitely variable • Taper: 7/24, NT40 • Front bearing diameter: 70 mm (2.76 in) • Feedrates: • Rapid (X/Y): 36 m/min (1417 ipm) • Rapid (Z): 30 m/min (1181 ipm) • Cutting feed (X/Y/Z): 10 m/min (394 ipm) • ATC: • Tool shank: MAS BT40 • Pull-stud: MAS 2 • Magazine capacity: 20 tools [optional: 32 or 48 tools] • Max tool diameter with adjacent tools: 90 mm (3.54 in) • Max tool diameter without adjacent tools: 125 mm (4.92 in) • Max tool length: 250 mm (9.84 in) Lsdpeyk Eyvjfx Ab Tjhc • Tool selection: Memory random • Motors: • Main spindle drive: • 7.7/5.5 kW (10.27/7.5 hp), 30 min/continuous, for 50–1100 min⁻1 • 11/7.5 kW (15/10 hp), 10 min/continuous, for 1101–7000 min⁻1 • Feed motors: X/Y: 3.0 kW; Z: 4.0 kW Dimensions Machine Depth 2380 mm

Condition: used, Year of construction: 2001, x-travel 560 mm y-travel 460 mm z-travel 450 mm Lhodpfjyi Hv Njx Ab Toc Control OSP U10 M total power requirement 7,5 kW weight of the machine ca. 5 t

Condition: used, Year of construction: 1989, x-travel 650 mm y-travel 410 mm z-travel 450 mm Lhsdpsx U A Rnsfx Ab Tsc travel x vor 1000 mm control mc4va

Condition: good (used), Year of construction: 2004, Opportunity to buy a 5 axis OKUMA machining center with EROWA automation. Including: EROWA Robot Easy automatic loading cell Chip conveyor Heavier coolant pump Higher Spindle speed Automatic measurement system for tool length, diameter setting, and tool breakage detection with a Renishaw laser Automatic measurement function, Renishaw MP10, BT40 Full technical specifications in the attached document. This machine is in very good condition and can be inspected under power upon appointment. Availability: 03/2026 CNC control Okuma OSP-E100M X-axis 762 mm Y axis 460mm Z axis 460mm C axis 360° Lsdpfxoyfht Uo Ab Tehc Table size 400 mm Table load 300 kg Spindle mounting BT40 Big plus spindle Tool changer capacity 32 positions Spindle speed 50-15,000 rpm Spindle hours approx 42000h Cutting hours approx. 38000h Please note: The information on this page has been obtained to the best of our ability and belief. This information is provided in good faith, but its accuracy is not guaranteed. Accordingly, this information is not binding and does not constitute a contractual condition. We recommend that you check all essential details during an inspection of the machine. To save unnecessary travel costs for our customers, in most cases we recommend organizing a live video inspection.

Condition: used, Year of construction: 1988, operating hours: 23,103 h, functionality: fully functional, travel distance X-axis: 652 mm, travel distance Y-axis: 412 mm, travel distance Z-axis: 452 mm, feed length X-axis: 652 mm, feed length Y-axis: 412 mm, feed length Z-axis: 452 mm, controller manufacturer: Okuma, controller model: OSP 5000, table width: 500 mm, table length: 1,000 mm, rotational speed (max.): 6,000 rpm, spindle speed (min.): 6,000 rpm, spindle speed (max.): 6,000 rpm, spindle nose: BT40, number of slots in tool magazine: 20, We are offering this used Okuma MC-4VA machining centre, year of manufacture 1988. Manufacturer: Okuma Model: MC-4VA Machine type: Vertical machining centre 3-axis CNC milling machine Travels: X-axis: 652mm Y-axis: 412mm Z-axis: 452mm Lhjdpfxsx Saybe Ab Tjc Spindle speed: 6000 rpm / 2 gear stages Tool changer: 20 tools Tool holder: BT40 Operating hours: 23,103 Control: OSP 5000 Programming: ISO code or IGF Data transfer: RS 232 The machine can be inspected under power. If you have any questions or need further information, please feel free to send us a message or give us a call.

Condition: excellent (used), Year of construction: 1999, X-axis 762 mm Y-axis 460 mm Z-axis 450 mm Working area 1,000 x 460 mm Spindle speed 7,000 rpm Tool holder SK40 Drive power 7 kW Weight 5,500 kg Incl. 2-position pallet changer Lhedsx Ek Ngspfx Ab Tsc Incl. internal coolant supply (IKZ) Incl. complete documentation