JINSE Tactical Bipod Folding Spring Return 13-21 inches with Adapter High Tech Durable Aluminum Construction Adjustable height & foldable arms with spring tension, leg height: 13 to 21 inches Posi-Lock legs provide extremely solid, exceptionally accurate shooting support Durable with new design high quality that you can quickly attaches to sling swivel stud Clever dual mounting - Picatinny rail