OPS INC™ NSWR Collar – DD RIS II Compatible

This is a modified MOD 0 collar featuring the same external dimensions, but the internal step has been set back slightly. It allows you to use a 15.1″ barrel with a Daniel Defense RIS II rail. You must use an NT4 spacer on the muzzle to get the correct spacing with the brake. The set screw has been moved to the rear to allow better access around the rail.

NT4 spacers are available here from ADCO