The Magpul UCS (Universal Carbine Stock) is designed to be the ideal supplement to the vast array of firearms utilizing a vertical M1913 Picatinny rail on the rear of the receiver for stock fitment. To accommodate the wide variety of charging handles styles, ejection port locations, and control locations, the UCS features a reversible hinge for left and right folding configurations, and five degrees of drop for clearance. Specifications for Magpul Industries Universal Carbine Stock, Fits 1913 Picatinny Rail, Side Folding, Adjustable Length of Pull, Matte Finish: Manufacturer: Magpul Industries Additional Features: Stock Fit: 1913 Picatinny Rail Case Finish: Matte Blade Finish: Matte Finish: Matte Features of Magpul Industries Universal Carbine Stock, Fits 1913 Picatinny Rail, Side Folding, Adjustable Length of Pull, Matte Finish: Six (6) Position, Push-Button LOP Adjustment Allows Three 3 of Total Adjustment" Package Contents: Magpul Industries Universal Carbine Stock, Fits 1913 Picatinny Rail, Side Folding, Adjustable Length of Pull, Matte Finish