Yankee Hill Machine Universal Suppressor Mount Coverts HUB Mount to Direct Thread M13.5x1 LH Black. 375"-24 HUB Direct Thread Mount will convert HUB compatible suppressors to a direct thread mounting system. To install simply remove your existing mount mechanism from your suppressor and thread on their HUB Direct Thread Mount using a 3/4" open end wrench. Then simply thread the suppressor onto your barrel. 17-4PH Heat Treated Material. Melonite QPQ Finish. 1.375"-24 Mounting Threads. Weight: 1.7 oz. Specifications for Yankee Hill Machine HUB Direct Thread Mount: Manufacturer: Yankee Hill Machine Color: Black Finish: Oxide Condition Quality: Excellent Caliber: .45 ACP Features of Yankee Hill Machine HUB Direct Thread Mount: 17-4PH Heat Treated Material Package Contents: Yankee Hill Machine HUB Direct Thread Mount