The BT33 Tube Rail Kit consists of a Steel Bar Nut, designed to fit inside free float tubes, and a low profile 1913 Picatinny rail 2.05" long with a 1.00" radius back and a center-to-center spacing of 1.602 between the holes.
The BT33 is installed with the Steel Bar Nut inside the free float tube and the 1913 Picatinny rail on the outside with the matching holes aligned. Fastened together, they allow the attaching of the Atlas Bipod or other accessories to free float tubes.
Machined to Picatinny rail standards from 6061-T6 aluminum with Mil-Spec Type III Class 2 finish. Manganese phosphate finish on the steel bar nut. Hardware included. Available in black only.