Depends, are you talking non-xtorq or xtorq saws. x torq 365 and 372's are same, only difference is baffles in 365's transfers, both 70cc. saws. Non has 365/371/372/375 on same lower end. 371 has no gussets in clutch side case, 372 has 2 gussets. 365 is a one ring piston. 371 came in one ring and two ring pistons. non epa 372 has one ring also, epa 372 two rings, depends on year of production. Do not take this as gospel, just what I have seen. Sure others know a lot more.