Step 1: Remove your SIM tray from your iPhone 4S.
Step 2: Place the R-SIM in the holder that comes with it, and place your SIM card from your desired GSM provider on top of the R-SIM.
Step 3: Place the combined SIM tray and R-SIM + SIM card in your iPhone 4S and wait until you see the carrier name for the SIM card you wish to use.
Since there’s currently no version of UltraSn0w that works with jailbroken iPhone 4S’ unlocking options aren’t nearly as plentiful as they have been on pre-4S devices.
The R-SIM is by far your best bet for using your factory locked iPhone 4S on other carriers outside of purchasing a factory unlocked phone.
What’s even better is that no 112 dialing is required. The version 2 of the device was just released, and it’s literally a plug and play device.
You can purchase your own R-SIM at Each Supplier’s website.