This 1.375"-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. 17-4PH Heat Treated Material. Melonite QPQ Finish. 1.375"-24 Mounting Threads. Weight: 1.7 oz.