which ios 2620xm ans a 3640

ToddB

planning on useing for CUCME CME 4.1, not sure which one to load so many.
was thinking c2600-adventerprisek9_ivs-mz.124-15.T13.bin for my 2620's
for the 3640 I'm not to sure seen c3640-ik9o3s-mz.124-7h.bin thoughts???????????