Mid-Length; Four anti-rotation QD sockets for push button swivels; High quality 1913 mil spec rails, T-marked for accessory location; Billet machined from 6061 aluminum and hard coat anodized; Complete install in minutes, removal of delta ring is required; Incredibly lightweight, extremely solid lock-up with monolithic type continuous top rail; Works with most well known piston systems including STAG, CMMG, ADAMS and Smith & Wesson to name a few; 100% Made in the U.S.A.; Black Finish; Lifetime Warranty