What you call that little thing, you stick any key in and make a mold print of it, and then make replica key.

Question

its like the size of match box

Answer 1

Key mold

http://www.instructables.com/id/Je-suis-...

Answer 2

You do understand, don't you, that all it does is make an image of the key and you still have to have key blank(s) and files and the chance you can make a working key in one attempt is very low, so you have to be able to try the key, etc.