Series 20 Linear Hydraulic Shock Absorber Features: Single Or Double Acting Constant Force Optional Mounting Choice of Bore And Stroke Completely Self-Contained Zero Maintenance Capacities To 30,000 Inch Pounds Part NumberABCDEFGH 50051 1/4"2 1/2"7/16"2"7 9/16"12 1/2"3/4"1/2" 51543"2 1/2"1-204"12 1/8"23 5/16"1 7/16"1 1/4" 51703/4"1 1/4"3/8"7/8"4 13/16"7 3/8".44"1/2" 51871"4"1/4"1 1/8"7 3/4"14 3/4".7".190" & .250" Part NumberMax. CapacityMax. Velocity 50052,000/lbs6 ft./sec 515430,000/lbs.8 ft./sec