What part of the gearbox is this?
 

Hey,

So I recently did a spring change on my G&G CM16 Raider with a Version 2 gearbox. I closed it up, tested it, and it works. I noticed afterward a small silver circle plate about one centimeter in diameter was left out. What is this part and is it important?

Thanks!

A shim, and while not likely critical, the gearbox will work more effectively with a proper shim placement.

picture?
if it's a solid plate, could be the motor height adjustment disc

i think thats a shim...its normally on the gears...
It won't mess things up, but it helps the gears to take less stress if placed correctly...

this

It looks like a tiny dime.
 

It looks like a tiny dime, no hole in the middle just a solid silver disk as big as my pinky nail.

yeah probably the motor shim. It goes between the bottom of the motor and the adjustment screw