牙型： 螺旋 （必须带螺旋小齿轮使用）
this is a very nice gear! strait and true, seems very solid, only have a couple test hops with it, but runs nice and smooth!
great fit on my 450 PRO!
will add another on my next order for back-up, should the nasty happen!This is dirt cheap!! Very good deal.
Perfect for "practice" use on TREX 450.
Radial run out is not perfect and the gear mesh changes from one spot to another, but it does not bother me at all: it does the job.Appear to run true, sad HK dont sell the pinions as wellThe quality of the gear is very good. I had my doubts that the colored material may have the draw back to be weaker than 'normal' gears - but not. The easily take the torque of my multi-blade helis. Please clean the pinion (you need a helical pinion - a normal pinion does not work) before you use it so that the gear doesn't get dark. Good quality and good sound.