(2) 17 inch 40 lbs Gas Prop Lift Springs Rod Struts Heavy Duty Tool Box Lid Top RV Pair Red Hound Auto Gas Charged Lift Supports Pair Open Length: 17 in; compressed: 10.25 inches Stroke Length: 6.75 inches Rod Diameter: 6mm || Force: 40 lbs. Compatible with 10mm Ball Mounts