How do you know which SIM Card is for Which Phone?

[Bbeelzebub]

I ordered two phones and they just arrived.

How do I tell which SIM card is which line? I don't want to activate a phone for somebody that isn't home at the moment by accident.

 

[Bbeelzebub]

Nevermind. Sorry. I just found a letter inside that shows the phone number for that particular phone. Thanks.