You can remove/install M4 castle nuts. The castle nut wrench slips over the castle nut and nearly encompasses the castle nut for a more secure fit. Makes for assembling/installing collapsible stock buffer tubes a very easy task as well.
The other end of the wrench is for installing/removing A2 Rifle buffer tubes (¾”)”.
1/2″ and 3/8″ drive compatible, for torquing your barrel nuts to the proper torque specifications.