question about straight talk and iphone 4s

[lnelson]

Hi,
I just got a used iphone 4s with sim card from someone used. I want to order the straight talk sim card in hopes that it will work. online it ask if I want a t-mobile compatible or At&t compatible...then asks about size of sim card...it looks very, very small do I order the micro.

Hoping this works.

 

[cjnnewman]

Is the 4s carrier unlocked? If not it won't work with straight talk. You'll need to call the carrier it's locked too and get it unlocked.