JK Armament Booster/3 Lug Adapter 1.180x24 Black. It's made to adapt your favorite pistol booster or 3 Lug mount to your JK 155 suppressor or to any other industry standard HUB mount 1.37524 TPI (1-3/824 TPI) threaded suppressor. Machined from 7075 billet aluminum and Type III Hardcoat anodized the JK 155 Booster/3 Lug Adapter comes in three internal thread sizes to fit pistol boosters and 3 Lug mounts from many different companies (see compatibility list below). Specifications for JK Armament Booster/3 Lug Adapter: Manufacturer: JK Armament Fabric/Material: Aluminum Color: Black Finish: Anodized Weight: 0.5 oz Package Contents: JK Armament Booster/3 Lug Adapter JK Armament JK155LTA80: Booster/3 Lug Adapter 1.180x24 Black