The Condor series phones have two numbers in the model number such as i55sr, i85s, i95cl, etc. The Falcon series phones have a three numbers in the model number such as i205, i275, i605, etc. All new Nextel phones are Falcon series phones.
The
sim cards for these phones will NOT work in each other. One is a 32bit one is 64. If you are upgrading from one of the old condors then you will have to go to a service center and get a new
sim. If you are upgrading from a Falcon to another Falcon then you are fine just pull out your
sim and put it in the other phone.