Wheeler AR Armorer's Bench Block -Specifically designed for AR-15 assembly and disassembly, the AR-15 Bench Block is the perfect tool. Made of extremely durable, non-marring urethane to protect the finish of your firearms and last for years. It features a variety of notches, grooves, and holes on both sides and is ideally suited for the upper receiver, lower receiver, front sight and charging handle of an AR-15. Positions the upper receiver, lower receiver, front sight, and charging handle for maintenance or assemblyDurable non-marring urethane material to protect gun finishDesigned to assist in all aspects of an AR-15 build