Brand new, never used - B&T/Surefire muzzle device compatible titanium suppressor HUB mount. This adapter will allow you to put any HUB compatible suppressor onto Surefire muzzle devices, including 5.56 muzzle devices.
Lowest I've found them for online is $258 (example screenshots in pictures), but they're all out of stock.
My asking price is $215. Located in Layton, UT. Willing to ship.
Description below is taken straight from the manufacturer if you want more details.
"The Rotex-SF HUB is fully compatible with all 1.375x24TPI HUB compatible suppressors on the market today and is constructed of Titanium and stainless steel components. This HUB is compatible with all B&T Rotex flash hiders, as well as all SOCOM flash hiders, muzzle brakes, and hybrid muzzle devices. The HUB is simply threaded into compatible suppressors and snugged up with a spanner wrench. HUB assemblies can be semi-permanently attached using Rocksett or other thread locking compounds should the end user desire."