The Primary Arms High Cantilever Mount will raise most 30MM tube red dot sights (Aimpoint, Vortex, Primary Arms, etc.) to allow for a lower 1/3rd cowitness. A lower 1/3rd co-witness places the red dot in the bottom part of the scope tube when aiming down the iron sights. This allows a less obstructed view of the entire scope tube when using the red dot instead of the iron sights. This tough mount features a lifetime warranty.Features:30mm tube diameterMounts to standard picatinny railAluminum construction