Armorer's wrench for use in assembling AR-style firearms. A must-have for any hobbyist looking to start their first AR-15 build. The wrench features different heads and grooves for attaching various parts of an AR. Included on the wrench are sockets for tightening the castle nut, barrel nut and muzzle device. The wrench also features a .410 choke remover for use with the ATI .410 upper receiver. Factory blemish models have superficial defects that did not pass quality inspection but are otherwise functionally perfect.