Originally designed for the AR15 type
Airsoft guns, this mounts on-top of the receiver rail and provides a
25mm (1 in.) higher rail for lifting any aiming devices like a red-dot
sight higher, making it more comfortable for shooters wearing full face
masks. It is perfectly centered on the top rail and features a
see-through tunnel, allowing the use of back up fixed sights. 2 mounting
screws are included to secure certain sights systems which features
matching threaded holes.