The MCD16 fits polymer magazines, doubling their available ammunition capacity and allowing for faster reloading. Wide gap between magazines allows for quicker magazine changes. Made of lightweight, light-density polymer. Improved durable design won't scratch or deform magazines. Easy-to-use screw-tightened design. No gunsmithing required. Lifetime warranty. Made in Israel. Weighs only 0.13 lbs. Dimensions: 7"H x 5"W.