The new BT17 - 4" 1913 Rail will accommodate hole patterns with a center to center spacing of 2.2 – 3.5" with a FLAT base to accommodate flat surfaces. A standard sling stud and Sling Stud spacer can be used as one fastener or two Button head machine screws can be used, NO HARDWARE IS INCLUDED (see BT1517
) to attach this rail to the forearm of standard rifle stocks. The BT17 can also be attached to a horizontal surface on the Butt section to attach our BR12 or BT13 Precision Rail Monopods. The BT17 also has a flush cup for that style of sling swivels.