BLACKHAWK Omnivore Surefire X300A Multi-Fit Holster, Surefire X300A, Belt Holster, Left Hand, Black/Tan, Fits More Than 150 Styles of Semi-Automatic Handguns with Accessory Rail, Hard, Thumb Activated Retention Mechanism 419001BCL Multiple holsters for multiple handguns is no longer an issue. The Blackhawk Omnivore is a multi-fit holster that accommodates more than 150 styles of semi-automatic handguns with an accessory rail. The active retention mechanism locks onto Blackhawk's proprietary Rail Attachment Device, not the frame of the handgun. A thumb release disengages the locking mechanism when drawing the handgun.