I know there are a few threads on WHERE to buy these and i have looked but i really can't afford $40 for a teething necklace at the moment, there are some on e-bay going for around $20 with free postage so wanted to know what to look for so if i do decide to get one i don't get ripped off.

A friend got one off e-bay and she's REALLY happy with it, i just want to know what you all suggest... TIA