New Accupart 1/4" NPT ST-4 Commercial Truck Air Brake Pressure Relief Valves, 250 PSI Relief Pressure, Without Adapter, Part Number ST-4 or ST4.  Each bid quantity is for One (1) Valve.  You may bid / buy any number of lots, up to the total quantity available above.

These were purchased at a lost freight sale last year, and they are brand new, sealed in plastic, and in the original small factory boxes.  We overpackaged the little boxes in heavy Ziplok bags.

NOTE: Most older truck compressors using the ST-4 relief valve will require a 1/2" NPT OD x 1/14 NPT ID bushing (not included). Several brake part suppliers have now started offering the ST-4 in 1/4" NPT threads, since you don't really need a relief valve the size of your thumb to regulate pressure. These use half the amount of material and do the same thing as the 1/2" variety. Once you have an adapter bushing (about $2.50) installed, you can forego the more expensive 1/2" valves from here on.

According to the calipers:

Overall length: 1.320 " 33.55 MM

Thread length: .413" / 10.49 MM

Valve face diameter: .546" / 13.86 MM

Hex size: .625" (5/8") / 15.87 MM

Threads: 1/4" NPT (National Pipe Thread)

Part Number Cross Reference (According to Various Online Sources, Please Verify):

Cross Reference

Automann: 170.131081
Bendix: 109914
Bendix: 1245572
Bendix: 131081
Bendix: 131081BXW
Bendix: 745131081
Bendix: 800154BXW
Bendix: BEN131081
Bendix: BW 131081
Bendix: BW800154
Bendix: BW 800154
Bendix: BW109914
Bendix: BX109914
Bendix: BX800154
Bendix: BXW131081
Chelsea: 800154
Euclid: E-BN131081N
Fleetcraft: FC131081
Fleetrite: FLTBV081
Freightliner: BW131081
Genuine Newstar: BER-131081
Genuine Newstar: S-C645
Genuine Newstar: SC645
Genuine Newstar: SNS-SC645
Mack: 745-131081
MCI: 4L-17-3
Meritor: R955131081
Meritor: R955131081N
Meritor: TDAR955131081N
Navistar: 3513-051-C1
Navistar: BEN13108
Navistar: BAN131081
Navistar: BX131081
Navistar: ZAC131081
OE Aftermarket: 700154
OE Aftermarket: BC645GRP
OE Aftermarket: BS645GRP
PAI: 5238
PAI: 52380
PAI: EM52380
PAI: LSV-5238
Power Products: 131081P
Rockwell International: EBN131081N
Tectran: 14490
Tectran: TV131081
Volvo Truck: 3969352