This Spigot Mount is designed to be used with the MPA BA Lite Chassis and or Rifle and our newer BA Chassis and Comp Chassis.. It is installed by removing the picatinny rail from the existing chassis, installing that rail on the spigot mount, sliding into the slot on the face of the Chassis and attaching with the supplied Flat Head Cap Screws. The end user can also install a sling stud into one of the 3 10-32 threaded holes on this mount.
The rail shown is not included. However, the rail that is on the existing chassis will fit this spigot perfectly.
For Standard BA Chassis and Comp chassis, if yours has the oblong slot cut in the front of the fore-end, then it will accept the spigot mount. This change was made in the summer of 2016 to the Standard and Comp Chassis.