Accumulator Repair Kit, Operating Temp. Range -20 to 165 Degrees F for Oil, 32 to 165 Degrees F for Water and Water-Glycol, Compatible With Accumulator Type Piston, For Use With 4WB51, 4WB54, 4WB57, Includes (2) End Cap O-Rings with (2) Back-up Washers, (2) PTFE Rings, and Gas Valve O-Ring, Buna V-O-Ring Piston Seals with (2) Back-up Washers