The Fenix ALG-15 Picatinny Rail Mount, is a great solution for mounting a flashlight to a rifle with a Picatinny rail. The quick release roller allows you to mount a flashlight for a secure fit. Made of hard-anodized aluminum, this mount is strong and lightweight-perfect for harsh conditions where durability counts. Features : Mounts to Picatinny Rails (MIL-STD-1913) "Adjustable Diameter Allows you to use Any Flashlight that is 0.925"-1.02"" Anodized Finish