All of these power systems use the same motor at different gear ratios. GWS says not to load them over about 12 amps. These are 7.2 S-400 motors. Although GWS normally reccomends these for 2S or 7-8 Nimh Nicad cells. They work well at 3S (or 10 round cells) if you keep the amps to 12 or less. they are best utilized at 8-12 amps range. No prop amp load chart is available for these.