The Syma S107 helicopter is amazing - anyone who owns one will attest to that. It has great stability and is a complete pleasure to fly. It can also take quite a bit of punishment and still survive!
If you're like me, and a bit brutal with yours - you might end up damaging the blades. In my case, I was being lazy and tried to take off from a crash landed position up against some furnature. Doing this can damage your blades!
These spare blades were delivered incredibly prompty, and with the aid of a small screwdriver (like you might use for repairing glasses), I had the blades changed in no time.
These blades were slightly thicker than the ones on my helicopter originally, so they are less floppy than the original. It doesn't make any difference to flying if you start with them spread out properly (for balance).
Stiffer blades might mean the heli has a little more potential for damaging things it crashes into, but so far I've not had any trouble at all.