Pro-x -
STD / A - 65.94MM
STD / B - 65.95MM
STD / C - 65.96MM
Wiseco -
One size only for std bore - the catalog says 66MM the box says 65.??mm
Kawasaki-
Same as wiseco, don't know the size
Having the option I'd use the Pro-x, from what I've seen there a better made piston, it a ART piston which is the same as many OEM's. I use a wiseco in my 220 - the stock one sucks and no other after market is made for the 220 other than the wiseco, so the option are limited.