Leapers, Inc. - UTG M-LOK Offset Flashlight Ring Mount, Low Profile, Comes with Two Inserts to fit 27mm, 25.4mm (1), or 20mm, Flashlight Tube Diameters, Black Finish, Includes M-LOK Steel Locking Nuts, Screws, and Allen Wrench for Simple and User Friendly Installation, No Gunsmithing Required RG-FL27MC This is a UTG M-Lok offset flashlight ring mount. It is low profile" 3.47" in length" and comes with two inserts to fit 27mm" 25.4mm (1") or 20mm flashlight tube diameters. Includes M-LOK steel locking nuts" screws and Allen wrench for user friendly installation.