This is a BLACKHAWK Paddle Holster known as the SERPA, model 413507BK-R.
Designed for civilian concealed carry or range use" the SERPA Sportster Holster is constructed of injection molded polymer for long-lasting durability. It features the same dependable SERPA technology but is specifically tailored for civilian operation. Features passive retention detent adjustment screw and speed cut design for rapid draw" target acquisition and re-holstering.
Features:
SERPA patented Auto-Lock technology
Fits Shoulder, S.T.R.I.K.E., Quick Disconnect and Tactical Holster Platforms
L shaped button which is optimized for security and performance
Right hand
Fits Springfield XD