We received a stock of these propellers accidentally and we don't recommend flying with them unless you have a lightweight and low powered aircraft. They are very thin, very flexible and do not withstand much more than 50 watts before the blades flatten out and vibrate in a rather spectacular fashion.
We have found they are excellent for mixing epoxy and spreading warm cream cheese on bagels.
Seriously though, we actually found a fun use for these things. They make excellent Whirligigs! We are not sure if this is the official name but it sure beats "propeller on a stick"
To make your very own Whirligig, purchase one or two of these props and a stick of the carbon tube listed below, cut the tube in half and wrap a piece of masking tape around one end (so the propeller friction fits on) and this thing will keep kids, big and small entertained for hours on end. :)
If you also would like to purchase the carbon tube used for building a Whirligig, click on the link below.