JUST FOR KICKS-If you have a os 46 AX, try the APC 12.25x3.75, this prop is so much fun, pulls like a truck, will slow the plane down the minute you drop the throttle, the clearance may be an issue but what fun. I change the landing gear on my 40 to the 4* 60, Little taller, the the stock 40 gear seems to flatten out right away. Just an idea to have some fun with.