The ERGO lower magazine block is the perfect accessory for your gunsmithing bench. Constructed of high strength reinforced nylon it will withstand years of use. This block is designed to hold an AR-15 lower receiver, using the magazine well and magazine catch. The mag block is an essential "third hand" for cleaning and light maintenance tasks. The mag block is easily attached to the bench with screws or bolts through two pre-drilled holes in the base for permanent installation. Or it can clamp to a solid bench top with two sturdy C-clamps for a portable or temporary solution. This block will also work with firearms that accept AR-15 pattern magazines, such as the FN SCAR 16, HK 416, or SIG 556.