I saw this lot on marketplace yesterday with only 1 photo but I could see 2 of the chassis so I jumped on it. All told there are 6 chassis in various states of dress 40ish motors, 3 pistol transmitters, 8 or more twin stick transmitters, receivers, servos, only 1 or 2 speed controllers, 1 body, and a bunch of other stuff. Tomorrow if I have time I will start to organize, catalog and test everything.
Cleans the commutator. ~~It’s a little honing stone that you inserted where one of the brushes was usually located that cleans off the carbon buildup.~~
I replied without actually looking at the picture 😅 That looks like a power supply for running the motor during the process. There was a fair bit of “voodoo” regarding motor performance, breaking your motors in, clocking the bell to adjust timing, etc.