LVLing 1 Inch Offset Adjustable 180 Degree Angle High Abrasion Resistance Polypropylene Composites 1 Inch Ring Side Mount for Flashlight/Laser/Scope Ergonomic design gives easy access to on/off switches for Flashlights, Lasers, or Red Dot sights, Scope This was designed to fit a 21mm picatinny rail system Polypropylene Composites A full 180-degree adjustment 1 Inch (25.4mm) diameter