Determining the length of your gas system: measure the distance from the rear of the gas block to the front of the receiver. If it is approximately 12 ½” it is a rifle length system, if it is approximately 9” it is a Midlength and 7” for a Carbine length.
– 308 Rifles: There are two basic types of 308 “size” AR rifles, often referred to as DPMS or Armalite “compatible” rifles. The parts, magazines etc do not interchange. For an easy way to differentiate between the two styles of rifles, look at the rear bottom of the upper receiver. A DPMS compatible rifle has a rounded edge while an Armalite has an angled edge. We offer a coupler nut for both types. DPMS #15060 with a 1 7/16″-16 TPI and Armalite #15061 with a 1 7/16″-18 TPI.
– Forends work with all barrel types that will work with a standard Delta ring.
– Will not fit rifles with Piston Gas Systems.
– Will fit older model ARs and M-16s with triangular shaped handguard.
– Coupler Nut Torque specs: 30-80 ft/lbs
– Made of 6061 aircraft aluminum with a molded non-slip elastomer layer on the outside.