PRE-ORDER: Currently our muzzle devices and HUB adapter are being sold on pre-order status. We have sold out of our first production run of these parts, but our machines are scheduled to make more over the next 3 weeks.  We will ship your orders on a first come first served basis.We promise it'll be worth the wait!ABOUT:Siege STRONGHOLD - Q Plan-B Compatible - HUB AdapterUses Siege Spanner Wrench or HEX to be secured in a bench vice.SPECS:Thread Pitch: 1.375x24 / BRAVOFinish: Nitride FinishWeight: 1.9oz