We have a SIM cutter (a special machine designed specifically for making micro SIMs) to turn a regular T-Mobile SIM card into a micro SIM (which is required for the Apple iPhone 4 only).

Because T-Mobile do not sell the iPhone in the USA, their SIM cards do not come as micro SIMs and need to be cut down to a micro SIM using a SIM cutter before they can be used in an Apple iPhone 4. You will not be able to buy a micro SIM directly form T-Mobile so if you're travelling to the USA with an iPhone 4 you will need to buy your SIM from us before you travel.

The Apple iPhone 3 and iPhone 3Gs use regular SIM cards and you only need a micro SIM if you have an Apple iPhone 4.