Exlusive optical rail for the FNV design M-lok UZI handguards:
Long
Short
Tri-rail
Mounts over the front of the dust cover, between the charging handle and the front sight post. It creates a low profile picatinny mount for compact red dots. It will touch the top cover to gain extra stability, so you will not be able to remove the top cover while this is installed. You will be able to use the iron sights when no optic is mounted on this rail.
Instructions: place it in the correct position you can see on the pictures and mount it with M-lok screw and nuts. When fastening the screw, pull the mount a little in outwards direction, that will help locking it. You are going to need 2 screws and 2 nuts, not included but you can get those for a dime on Aliexpress.