Precision Reflex Pri Armorers Barrel Nut Torq Wrench Black. AR15 barrel nuts. The wrench is constructed of 1018 steel with 5 alloy steel pins that are press fit and welded into the wrench handle. The handle accommodates a 3/8 or 1/2in drive torque wrench. The overall length of wrench is 12in and weights 1.3 lbs. The wrench has additional holes between the pins to help get the proper alignment of the gas tube. The wrench has a black oxide finish. The ID of the wrench is 1.2in. Specifications for Precision Reflex Pri Armorers Barrel Nut Torq Wrench: Manufacturer: Precision Reflex Fabric/Material: Steel Color: Black Condition: New Finish: Nitrite Gun Model: AR-15 Package Contents: Precision Reflex Pri Armorers Barrel Nut Torq Wrench What firearm models does the manufacturer say Precision Reflex Pri Armorers Barrel Nut Torq Wrench is compatible with? The manufacturer says that Precision Reflex Pri Armorers Barrel Nut Torq Wrench is compatible with AR-15Precision Reflex 05-0084: Pri Armorers Barrel Nut Torq Wrench Black