Suspa C16-21825 C1621825 15" Gas Prop, Quantity (2), Force is 28 Lbs per prop and Force per set is 56 Lbs,&nbsp; Suspa recommends to replace both struts at the same time, Camper Rear Window, Tonneau Cover Lift Supports, Window Lift Support, Struts Compressed Length (Center-to-Center): 9.25 in Extended Length (Center-to-Center): 14.7 in Force: 28 Lbs (Per Prop) Set of Two End Fittings: 10mm Nylon Ball Sockets