Griffin Armament 3 LUG Adapter .45CAL 16x1 LH Black. 45 3 Lug adapters are only compatible with the Griffin .45 3 Lug Interface Assembly. Made from 17-4ph stainless and Melonite QPQ treated. Specifications for Griffin Armament .45 Caliber 3Lug Barrel Adapters: Manufacturer: Griffin Armament Color: Black Finish: Melonite QPQ Fabric/Material: 17-4PH Stainless Steel Features of Griffin Armament .45 Caliber 3Lug Barrel Adapters Thread Pitch:.578 Caliber:.45 Thread Pitch:16x1mm LH Thread Pitch:5/8x24 Attachment System:3 Lug Type Of Part:3 Lug Package Contents: Griffin Armament .45 Caliber 3Lug Barrel Adapters Griffin Armament 3L45C161LH: 3 LUG Adapter .45CAL 16x1 LH Black