I personaly have had better luck with the APC series of electric slow flyer propellers!! They are fantastic, and theyre much more effecient!!!!! You will need to use the little spacer that comes with it and then add a piece of small fuel tubing inserted in the propeller to make it work due to the shaft openning being a bit larger than the gws props and not locking on the shaft liek the stock props do. This is also better since it gives your prop a bit of a shock protection in case you hit anything. Hope this helps Jon