The 16.5-12W like Chad stated or the 17-12.....These are the APC props.....If you want a ballistic missile the 16-12 works and works good for a break in type of application....The 17-10 regular tough to find not the narrow....its fairly new....Central has them....


Also the 16-13 works pretty well.


My preference goes to the 16.5-12W best overall acceleration and brakes....but its not the quiet choice....you will running 95-96db full open.....this busts the F3A noise rule.....But dial it back about 300rpm to around 8100 and its makes 92-93db and still has tons of power the as the 2 strokes at sea level.

This is of course on 30% cool Power heli Pro

Troy Newman