Threading and o-rings makes installation difficult
This barrel is a 3 piece system that is made exceptionally well. The barrel tip itself is a .700 bore which is available in several lengths from 10 to 16". The tip screws onto a stainless section which holds the back end. The back ends are sized differently (both a smal bore kit and a big bore kit are available. This makes a paint to barrel match simple.
The insert is left handed threading so that it tightens up differently. But if you tighten too much, the o-rings that seal the 3 parts together can squeeze out into the barrel. If you don't tighten it enough, the barrel unscrews when you thread it into the marker. The barrel kits come with a tool to help solve the problem, but it would be nice if it wasn't needed.
Great barrel. Less than a Freak set, accurate and quiet. The 9 is for the threading.