A PAIR(2) Leer Truck Tonneau cover gas strut spring lift 19.69" extended length x 11.85 " compressed length x 120 LB Pressure Extended Length: 19.69" (center to center of ball socket ends) Compressed Length: 11.85" Force: 120 pounds of pressure (Per Prop) End Fitting: 10mm Ball Socket and 10mm Ball Socket Set of Two