I have used other sim adaptors previously successfully, this one is extremely thin and easily breaks, would't risk it again. I used it to put a small sim into a Nokia 5800 which I took to India to use instead of my iPhone. The thing is very thin and I couldn't take it out from the slot, with all my attempts eventually it broke inside the phone. I had to find someone to unscrew the phone to get the bits of the adaptor that separated from the sim, and the sim out. The sim slot was completely damaged with all those procedures unfortunately..
it is an adapter with stickers on both side that you need to cut to keep the connection between sim card and phone ... first of all .. the sticker gets stuck in the sim card slot and is a single use product ... or for someone who does not plan to change sims between phones ... but then that according to me defeats the purpose of an adapter / converter. If it were to stay in one phone i would just get the right size sim from the network (free of charge!).