2.5″L x 1.5″W x 4H. Firearms with Picatinny rail system. Laser Class: Class IIIA. Maximum Output Power: less than 5mw, meets US safety guide. Please note that IR Laser Only Visible under Night Vision Device. Water resistant, shock/recoil proof. Windage and Elevation adjustable. Durable aerospace aluminum, coupled with a water tight design. Easy to control – Comes with wire cable remote control pressure pad switch. Please note that top rail CANNOT be removed. Item Dimensions L x W x H.