The Weaver medium Locking Rail Panel protects unused rails from damage while providing a gripping surface that shields the operator from weapon heat and sharp rail edges. Made of a tough ridged polymer and held in place by the patented Rail-Lok integral locking mechanism these low profile rail panels improve feel and weapon control. Medium Locking Rail Panel covers 3.2" of rail perfect for 1/2 coverage on an AR-15/M4 Carbine length fore end rail. Made in the USA.