The slimmest, low-profile GOPro rail mount is finally here--the INVADER. Cut from a single block of 6061 Aluminum, the INVADER clamps to any 1913 Picattiny rail with the turn of a screw and secures your GoPro camera with ease. It's designed to fit rails made correctly to the 1913 Picatinny standard and rails that are oversize and don't adhere to the standard. It may not fit all rails. Many accessories and rails are not made correctly. The INVADER XL is designed with larger clearances to fit rails that weren't made to the 1913 standard. Please see the forums for a live list of compatible guns and rail systems.