Yankee Hill HUB Direct Thread Mount 5/8''-24 Tpi 17-4 Stainless Steel Blac. 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 our HUB Direct Thread Mount using a 3/4" open end wrench then simply thread the suppressor onto your barrel. Specifications for Yankee Hill Machine HUB Direct Thread Mount System: Manufacturer: Yankee Hill Machine Caliber: .45 ACP Color: Black Finish: Oxide Condition: New Condition Quality: Excellent Condition Details: Other Features of Yankee Hill Machine HUB Direct Thread Mount System: 17-4PH Heat Treated Material Package Contents: Yankee Hill Machine HUB Direct Thread Mount System