These new GM pylons are quickly becoming very popular world wide. Our good friend Georgi in Bulgaria is producing these, along with his fine F5B props we also carry.
If you are tired of breaking your pylon props, try one of these. The cone size is a 30mm with a 3.2mm shaft, tightens securely with a grub screw. Once you cut the power and the blades retract, it will increase your speed with no drag from the free wheeling prop, making for some exciting downhill runs. This will change your flying!