Yankee Hill Machine sRx Q.D. Flash Hider Short Black Phosphate Steel with 11/16in-24 tpi for sRx Adapters. This Q.D. Flash Hider is compatible Q.D. Adapter/Mounting Interface attaches to the industry standard (HUB) 1-3/8 x 24 threads. It features an internal taper seal-in front of the threads-that locks your suppressor on and forms a tight seal to contain gasses while in-use. This means no gasses or debris can build up on the threads. The sRx Flash Hider must be paired with The YHM sRx Adapter (YHM-4400). The sRx Flash Hider adds minimal length and weight to the suppressor set up while also allowing you to reap all the benefits of the new YHM sRx System-when used in conjunction with The sRx Adapter. The full YHM sRx (Suppressor Rx) System will be the obvious choice for someone looking for a sleek low-profile suppressor set up-thats also built to withstand rigorous use. This is their prescription for the shooter who cares about the aesthetics of their build as well as its ease-of-use. Some of the exciting new benefits of the YHM sRx System are as follows: TIMELESS. (No need to shim/time to barrel). Small/low profile. No moving parts. Large taper in front of the threads allows for consistent mounting. Lighter than many Q.D. mounting offerings on the market. Can be permanently attached to firearm barrel needed. The YHM sRx System-just what the doctor ordered Specifications for Yankee Hill Machine sRx Q.D. Flash Hider: Manufacturer: Yankee Hill Machine Color: Black Finish: Phosphate Fabric/Material: Steel Gun Make: Universal Gun Model: Universal Condition: New Package Contents: Yankee Hill Machine sRx Q.D. Flash Hider Yankee Hill 444524B SRx Q.D. Flash Hider Short Black Phosphate Steel With 11/16''