Yankee Hill Machine R9: High-quality, superior performance, wallet-friendly. That\'s what you get with the YHM R9 suppressor. A 9mm suppressor with the capability of handling larger calibers while maintaining the rugged durability that you come to expect from YHM. It allows you, the shooter, to enjoy versatility across your entire arsenal all at a budget-friendly price. The R9 is capable of being used on a handgun in conjunction with the Nielsen Booster Assembly and accepts a full lineup of HUB mounting options. The R9 ships with a 1/2\" - 28 Direct Thread HUB Adapter, a HUB adapter wrench, and a 1.375\"-24 HUB spanner wrench.