Compatible with HoloSun series dot sights Firmly secures onto optic rails with screw on installation Strong and lightweight full metal construction Includes fittings and tools for use out of the box Compatible with standard 20mm picatinny rails Firmly tightens to prevent loosening from vibration or recoilSpecifications: Brand Atlas Custom WorksBuild Full MetalFunction HS Series Sight MountCompatibility HS Series Dot SightsFitment 20mm picatinny railsColor BLACK 1X T1 Optic Mount