The Blackhawk Single Mag Case provides quick and easy access to spare magazines while maintaining adequate retention. Using a built-in tension spring, the Blackhawk Single Mag Case hold magazines of various sizes securely in place. Made of durable injection molded polymer Adjustable belt-clip hook Accepts 9mm, .40, .45, 10mm, and .357 Sig mags The Blackhawk Single Mag Case uses an adjustable belt-clip hook to accommodate belts of different widths. Mfg: Blackhawk