Used Safety Valve for sale (14,590)

  • Sort results

  • Lowest price Highest price
  • Newest listings Oldest listings
  • Shortest distance Farthest distance
  • Newest year of manufacture Oldest year of manufacture
  • Latest update Oldest update
  • Manufacturer A to Z Manufacturer Z to A
  • Relevance
Lowest price
Price
Highest price
Price
Newest listings
Release date
Oldest listings
Release date
Shortest distance
Distance
Farthest distance
Distance
Newest year of manufacture
Year of construction
Oldest year of manufacture
Year of construction
Latest update
Update
Oldest update
Update
Manufacturer A to Z
Manufacturer
Manufacturer Z to A
Manufacturer
designation from A to Z
Description
designation from Z to A
Description
Model from A to Z
Model
Model from Z to A
Model
Lowest reference
Ref.No.
Highest reference
Ref.No.
Shortest runtime
Runtime
Longest duration
Runtime
Relevance
Relevance
Listing
Pneumatic actuator with valve AMG-PESCH SAF 30NC
Pneumatic actuator with valve AMG-PESCH SAF 30NC
Pneumatic actuator with valve AMG-PESCH SAF 30NC
Pneumatic actuator with valve AMG-PESCH SAF 30NC
Pneumatic actuator with valve AMG-PESCH SAF 30NC
Pneumatic actuator with valve AMG-PESCH SAF 30NC
Pneumatic actuator with valve AMG-PESCH SAF 30NC
more images
Netherlands Eindhoven
7,564 km

Pneumatic actuator with valve
AMG-PESCHSAF 30NC

Call
Listing
Control unit 1 SICK Sick Safety Relais FX3-XTIO84002 1
Control unit 1 SICK Sick Safety Relais FX3-XTIO84002 1
more images
Germany Offenbach am Main
7,839 km

Control unit 1
SICKSick Safety Relais FX3-XTIO84002 1

Call
Listing
5/2 way valve Bosch 0 820 038 955
5/2 way valve Bosch 0 820 038 955
5/2 way valve Bosch 0 820 038 955
5/2 way valve Bosch 0 820 038 955
more images
Germany Wiefelstede
7,607 km

5/2 way valve
Bosch0 820 038 955

Certified Dealer
Call
Listing
Glass cutting table for laminated safety glass (VSG) Hegla ProLam 37 inkl. EcoLam 60
Glass cutting table for laminated safety glass (VSG) Hegla ProLam 37 inkl. EcoLam 60
Glass cutting table for laminated safety glass (VSG) Hegla ProLam 37 inkl. EcoLam 60
Glass cutting table for laminated safety glass (VSG) Hegla ProLam 37 inkl. EcoLam 60
Glass cutting table for laminated safety glass (VSG) Hegla ProLam 37 inkl. EcoLam 60
more images
Germany Brunnthal
8,154 km

Glass cutting table for laminated safety glass (VSG)
HeglaProLam 37 inkl. EcoLam 60

Call
Listing
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
Dozer Caterpillar D 6 N LGP (Ripper valve + GPS preparation)
more images
Belgium Stabroek
7,507 km

Dozer
CaterpillarD 6 N LGP (Ripper valve + GPS preparation)

Certified Dealer
Call
Listing
Rotary valve TrennSo AS 600x1400-6
Rotary valve TrennSo AS 600x1400-6
Rotary valve TrennSo AS 600x1400-6
more images
Germany Meckesheim
7,894 km

Rotary valve
TrennSoAS 600x1400-6

Certified Dealer
Call
Listing
Automatic condensate separator, condensate drain, drainage valve KAESER Eco-Drain 13
Automatic condensate separator, condensate drain, drainage valve KAESER Eco-Drain 13
Automatic condensate separator, condensate drain, drainage valve KAESER Eco-Drain 13
Automatic condensate separator, condensate drain, drainage valve KAESER Eco-Drain 13
Automatic condensate separator, condensate drain, drainage valve KAESER Eco-Drain 13
Automatic condensate separator, condensate drain, drainage valve KAESER Eco-Drain 13
Automatic condensate separator, condensate drain, drainage valve KAESER Eco-Drain 13
more images
Germany Hessisch Lichtenau
7,826 km

Automatic condensate separator, condensate drain, drainage valve
KAESEREco-Drain 13

Certified Dealer
Call
Listing
Safety Light Curtain C4000 BASIC SICK C4000 BASIC
more images
Germany Bielefeld
7,707 km

Safety Light Curtain C4000 BASIC
SICKC4000 BASIC

Call
Listing
Way valve Herion** S6VH10G15900160V
Way valve Herion** S6VH10G15900160V
Way valve Herion** S6VH10G15900160V
Way valve Herion** S6VH10G15900160V
Way valve Herion** S6VH10G15900160V
more images
Germany Wiefelstede
7,607 km

Way valve
Herion**S6VH10G15900160V

Certified Dealer
Call
Listing
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
more images
Pöttmes
8,077 km

High top van
FiatDucato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera

Call
Listing
Safety workplace WIBO Jekt  Weiss TCRJO 180/98
Safety workplace WIBO Jekt  Weiss TCRJO 180/98
Safety workplace WIBO Jekt  Weiss TCRJO 180/98
Safety workplace WIBO Jekt  Weiss TCRJO 180/98
Safety workplace WIBO Jekt  Weiss TCRJO 180/98
more images
Germany Tönisvorst
7,631 km

Safety workplace
WIBO Jekt WeissTCRJO 180/98

Certified Dealer
Call
Listing
Rotary valve TrennSo AS 600x1400-6
Rotary valve TrennSo AS 600x1400-6
Rotary valve TrennSo AS 600x1400-6
more images
Germany Meckesheim
7,894 km

Rotary valve
TrennSoAS 600x1400-6

Certified Dealer
Call
Listing
2/2 way valve 321 K 1535 F03S. C00. 479 BOSCH 321K1535
2/2 way valve 321 K 1535 F03S. C00. 479 BOSCH 321K1535
2/2 way valve 321 K 1535 F03S. C00. 479 BOSCH 321K1535
2/2 way valve 321 K 1535 F03S. C00. 479 BOSCH 321K1535
2/2 way valve 321 K 1535 F03S. C00. 479 BOSCH 321K1535
2/2 way valve 321 K 1535 F03S. C00. 479 BOSCH 321K1535
2/2 way valve 321 K 1535 F03S. C00. 479 BOSCH 321K1535
more images
Germany Langen
7,612 km

2/2 way valve 321 K 1535 F03S. C00. 479
BOSCH321K1535

Call
Listing
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
Electric forklift - full cabin - 4th valve - ZVG STILL RX 60-25
more images
Germany Pulheim
7,673 km

Electric forklift - full cabin - 4th valve - ZVG
STILLRX 60-25

Certified Dealer
Call
Listing
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
With valve Cosen SH-4030
more images
Finland Salo
7,845 km

With valve
CosenSH-4030

Call
Listing
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
more images
Pöttmes
8,077 km

High top van
FiatDucato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera

Call
Listing
Servo valve unit MOOG D665-5703 & D661-5623C
Servo valve unit MOOG D665-5703 & D661-5623C
Servo valve unit MOOG D665-5703 & D661-5623C
Servo valve unit MOOG D665-5703 & D661-5623C
Servo valve unit MOOG D665-5703 & D661-5623C
Servo valve unit MOOG D665-5703 & D661-5623C
Servo valve unit MOOG D665-5703 & D661-5623C
Servo valve unit MOOG D665-5703 & D661-5623C
more images
Germany Borken
7,614 km

Servo valve unit
MOOGD665-5703 & D661-5623C

Call
Listing
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet Dasit Biopharma SafeFAST Classic 209D
more images
United Kingdom Duxford
7,214 km

Dasit Biopharma Faster SafeFAST Classic 209D Microbiological safety cabinet
Dasit BiopharmaSafeFAST Classic 209D

Call
Listing
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
Push-through safety device pallet rack SSI Schäfer / lichte Weite: 2.765 mm / Profilabmessung: C: 60x40x8 mm
more images
Germany Neukamperfehn
7,570 km

Push-through safety device pallet rack
SSI Schäfer / lichte Weite: 2.765 mm /Profilabmessung: C: 60x40x8 mm

Certified Dealer
Call
Listing
Electric forklift full cabin ZVG 4th valve STILL R 60-35
Electric forklift full cabin ZVG 4th valve STILL R 60-35
Electric forklift full cabin ZVG 4th valve STILL R 60-35
Electric forklift full cabin ZVG 4th valve STILL R 60-35
Electric forklift full cabin ZVG 4th valve STILL R 60-35
Electric forklift full cabin ZVG 4th valve STILL R 60-35
Electric forklift full cabin ZVG 4th valve STILL R 60-35
Electric forklift full cabin ZVG 4th valve STILL R 60-35
more images
Germany Pulheim
7,673 km

Electric forklift full cabin ZVG 4th valve
STILLR 60-35

Certified Dealer
Call
Listing
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
High top van Fiat Ducato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera
more images
Pöttmes
8,077 km

High top van
FiatDucato 35 MAXI L5H2 L4H2 180 15m³ Safety Kamera

Call
Siegel

Trust Seal

Dealers certified through Machineseeker

Trust Seal
Listing
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet ICN Biomedicals Gelaire BSB
more images
United Kingdom Duxford
7,214 km

ICN Biomedicals Flow Gelaire BSB Class 2 Safety Cabinet
ICN BiomedicalsGelaire BSB

Call
Listing
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
Envair Technology B102 Microbiological Safety Cabinet + Stand Envair Technology B102 +
more images
United Kingdom Duxford
7,214 km

Envair Technology B102 Microbiological Safety Cabinet + Stand
Envair TechnologyB102 +

Call
Listing
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
CAS Biomat 2 CAS Biomat 2 Microbiological Safety Cabinet
more images
United Kingdom Duxford
7,214 km

CAS
Biomat 2CAS Biomat 2 Microbiological Safety Cabinet

Call
Listing
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
Big Neat. F3-XIT Safety Cabinet Big Neat F3-XIT
more images
United Kingdom Duxford
7,214 km

Big Neat. F3-XIT Safety Cabinet
Big NeatF3-XIT

Call

This may be of interest to you

Biggest excavator

Photo gallery: The World's 10 biggest excavators

Machineseeker Auctions

Sales with maximum attention: Selected auction highlights

Extension Sponsor European Championship

Machineseeker agrees three-year extension as European Championship sponsor

Machinseeker Olympic Games

Olympic Games: Machineseeker supports “Team Germany” in Paris

Title sponsor EHF Champions League

Machineseeker remains title sponsor of the EHF Champions League

Tricks for buying used machines

10 valuable tricks for buying used machines online