1. Suitable for all popular non-adjustable GM type combination valves. 2. Used to lock the low pressure exhaust valve, so that the braking system on PV2/PV4 can exhaust quickly and easily 3. High-quality materials and durable 4. Specially designed for CPP proportional valve to prevent the combined valve from tripping 5. Fits for DISC DRUM PV2 and PV4 AC 172-1371 ect.
