Mestart Tactical Bipod OP-I Aluminium Foldable Adjustable Height Fits Picatinny Rail High Tech Durable Aluminum Construction with Light Weight Fits Picatinny Rail, 8.8 Ounces. Extendable Spring Powered Legs, Adjustable Height from 9 to 11 Inches. Unique Posi-lock Feature to Prevent from Tipping, Stable Rubberized Comfort Stand. User-Friendly Spring Operated,Double-Lock Clamp. Handy,Foldable Design for Portability and Storage.