It all depends on how you want to have that second number on the same phone. There are dual-SIM adapters for most phones out there. However, you would want to hide that inside of a case because the ribbon-like cable would stick out of your SIM slot for the second SIM unless you use one of the Bluetooth secondary SIM devices. This would also work like most phones, giving you what is called, dual standby, which means if you are on a call with one SIM, the other will go straight to voicemail or say you are not available.
