Picatinny Accessory Rail Mount. Designed for the undermount on the Government Model 1911 dustcover to enable fast, easy mounting of lights, lasers and other tactical gear. M1913 Picatinny MIL-STD with 4 cross slots CNC machined from solid billet. Equipped with three mounting holes for light duty and 3 - 6/40 x 1/2 screws. Drilling and tapping of your receiver is required. Welding or silver soldering is recommended for hard use situations. May also be altered by a competent gunsmith or machinist for top mounting of your slide or other tactical uses.