BLACKHAWK CQC SERPA Holster With Belt and Paddle Attachment, Fits Glock 21, S&W MP, Left Hand, Black 410513BK-L Featuring their patented SERPA Auto-Lock(TM) technology, the SERPA CQC Concealment Holster delivers a smooth draw, easy re-holster and unparalleled handgun security in a sleek package that is perfect for concealed carry. Features a passive retention detent adjustment screw. Rapid draw, target acquisition and reholstering are improved with the speed-cut design of the holster. They fit Shoulder, S.T.R.I.K.E., Quick Disconnect and Tactical Holster Platforms.