This is a three piece unit with a compressed moulded EDPM rubber sleeve over the inner tube (6061-T6 aluminium) and a 316 stainless steel nut holding the EDPM sleeve in place. This tube screws onto a thread on the outside of the barrel muzzle and is adjusted along that thread length until you find the sweet spot and lock it up at that point with a split nut/grub screw arrangement. This is the simplest type of tuner and also one of the most effective but requires the end of the barrel to be specially threaded long enough to allow for length wise adjustment. The front face of the tuner is engraved with 16 divisions that allow precise, repeatable adjustment against a witness mark on your barrel in the relevant position.
This thread would be machined onto the end of your barrel by your gunsmith or armourer and should be approximately 1.25″ long.
Other threads are available by request but remember the thread length has to be long enough to give you some adjustment range.
If your barrel is already threaded with a short ½”, 5/8″, 18mm or similar thread then you should consider using one of our other tuner designs that simply lock onto this thread and the adjustment length is built into the tuner rather than along the barrel.