I bought a set of these for my Tokyo Mauri P90 to replace the stock aluminum gears. I also replaced the piston with a Prometheus steel tooth high speed piston. Now I'm not sure if the pitch of the gears or the angle of engagement was off (I'm a machinist by trade), but even with me trying to cut down the edges of the teeth I couldn't get it to cycle completely. I would get about half a cycle and then it would bind. Now I don't know if this is simply because the gears aren't designed to operate with this particular type of piston or the fact that it doesn't work in my P90 (less likely). Even though they don't work for me and I ended up going back to my stock aluminum gears I can still tell that they are a good quality gear strength wise and as long as they work with your gearbox and piston I'm sure they would last a long time.
-Made of a strong steel that should (as long as they're properly shimmed) last a long time
-Doesn't fit a T.M. P90 with a Angel Custom Piston (may be an isolated indecent)
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