The BT46-NC model Atlas Bipod is part of their PSR Series. The "NC" stands for "No Clamp," meaning it requires any 17S size mount in order to attach to a firearm. The interface to install a clamp has a two hole pattern of 1.100" with 10/32 threads. It will also mount directly to their BT19 AI Spigot or BT70 M-LOK Adapter.The BT46-NC is comprised of 6061-T6 aluminum, except the strengthened inner legs which are made from 7075-T6 aluminum that are Mil-Spec Type III hard coat anodized with heat treated, stainless steel components. Includes two 10-32 x 3/8" flathead socket screws. Available in black only. FeaturesHeight Range: 5 - 9.4" (6.5" at 90deg)Preloaded Pan: 30 degreesPreloaded Cant: 30 degreesPosition Button 0.5" diameterFore and Aft pivot limiting Bosses5 leg positions: 0, 45, 90, 135 & 180 degreesNon-Rotating Legs: outer leg does not rotate around inner legLarger, stronger inner legsWeight: 11.42 ounces approx.Footprint: 8- 11"