[KenWittlief]

yeah, its in the rules that you can only use the suppled KOP compressor for your robot.

part of it is a safety issue. Compressor tanks tend to get water in them, and after a few years they must be discarded even though they look like new on the outside.

I would not want to be in the pits next to a team that dragged in some 30 year old compressor they got at a garage sale. Im sure thats not what your team intends to do, but FIRST has to draw the line somewhere.

So thats where they drew it: KOP compressor only.