Originally Posted by Karun97
can i use this firmware.10.5.A.0.230 Customized US ? I'am in INDIA.
Just flash 10.5.A.0.230 from the C6603, the only difference between the C6602 and C6603 is the support for lte(4g) which in your case(C6602) is not supported.
Flashing C6603 roms on your C6602 phone should work fine, it just ignores the additional lte(4g) modules meant for the C6603.
As bonus you'll have android 4.4.2 kitkat