Weighing less than 150 grams, this mount was specifically designed for law enforcement use on AR15 assault rifles and for use in dynamic shooting disciplines such as IPSC. The 56 mm extended version was developed to provide sufficient eye relief for all types of use. The shorter base of the mount also makes it easier to turn the adjusting ring for magnification. ERATAC One-Piece Ultralight Mount 1" Tube 0 MOA 37mm 146 high