That looks like one of my old chargers! The way its polished and cut. Polished using a scouring pad (if thats whats its called) in a dremmel holder bit to give the smooth yet slightly rough texture for the air to flow over (think golfball). Outlet Seal was removed and dremmelled out, but is fairly port matched to the outlet of charger so not to introduce a step. You wouldn't believe the amount of thought was going into our ones, even down to calculations, flow volume etc!
Could also be a Race Power Motorsport charger done by Andy Boakes as we did our chargers the same. Andy had about 3-4chargers himself as spares for the racer, Quinny had one aswell and I think a few more people had a few.
