The Blackhawk Double Magazine Case features a built-in tension spring that securely holds two double stack magazines of various sizes. It features an adjustable belt-clip hook that accommodates belts of different widths. FeaturesBuilt-in tension spring securely holds magazines of various sizesIncludes belt loops and belt clipCurved to waistline for slimmer profileFits 9mm/.40 cal/.45 cal/10mm/.357 Sig