Solid Construction: These ball bolts are made of metal materials with good wear and strength, zinc plated for increased durability. Standard Thread Size: Equipped with 5/16in‑18 threads, high compatibility with many existing connectors and fittings, easy installation and replacement. 12 Pcs Set: The gas lift support hardware kit includes 4pcs 13mm ball studs, 4pcs washers, 4pcs nylock nuts, high strength, long lifespan. Suitable for Gas Strut: Designed for gas lift support, can be used for car hood, trunk lid, door and other parts, to provide stable and support. Wide Application: Fit for Tool Boxes, RVs, Camper, Marine Shocks, Cabinets, Boats, Bed Hardware, Cars, Auto, Toy Box, Tonneau Covers, Hood Struts, Chute, Vehicle Window, Trailers, etc. Item Type: Ball Studs Material: Metal Ball Head Diameter: Approx. 13mm/0.51in Thread: 5/16in-18 Shank: 5/8in Fitment: Fit for Tool Boxes, RVs, Camper, Marine Shocks, Cabinets, Boats, Bed Hardware, Cars, Auto, Toy Box, Tonneau Covers, Hood Struts, Chute, Vehicle Window, Trailers, Trucks, Truck Boxes, Desks, Door Hatch, Trash Can Box and various other lift support needs Package List 4 x Ball Studs 4 x Washers 4 x Nylon Lock Nut