This is a San Tan Tactical Mag Release, model STT-MAGRB-RED.
The Ultra Grip Extended Magazine Release allows for quick" positive mag changes. The increased height profile along with the ultra grip texture eliminate the fear of accidental mag releases or the risk of catching on your gear. The Ultra Grip Extended Magazine Release is available in black" red and raw finish.
Features:
Ultra Grip Texture
Increased Height
7075-T6 Aluminum