Series 30 Bumper Type Hydraulic Shock Absorber Features: Single Action – Spring Return Completely Self Contained Pre-Engineered Orifice Choice of Bore and Stroke Zero Maintenance Optional Mounting Capacities to 60,000 Inch Lbs. Part NumberABCDEFGHIJKLMN 51631"1"1/2"2 3/8"4 3/4"6 1/4"*2"------- 51641.5"1"1"3"6 3/8"7 1/2"1 7/8"1/2"4 1/2"3 1/2"1/2"4"3"3/8-16" 51663"1.5"1 1/4"5"8"12 3/8"3/4"1/2"5 3/8"4 3/8"1/2"5 3/8"4 3/8"9/16" 51693"2"1 1/4"5"8 3/4"11 1/8"1"1/2"5 3/8"4 3/8"1/2"5 3/8"4 3/8"9/16" 6141-12"5"1 1/4"4"11 15/16"18 15/16"2 1/4"-5 1/2" BC4 7/8" -5 1/2" BC4 7/8" BC1/2"