A PAIR(2) RV Boat Nitro-Prop Gas Strut Spring Shock Lift Rod Piston 10" extended length x 7 " compressed length x 40 LB Pressure Extended Length: 10" (center to center of ball socket ends) Compressed Length: 7" Force: 40 pounds of pressure (Per Prop) End Fitting: 10mm Ball Socket and 10mm Ball Socket Set of Two