Nokia introduced 6310 phone in 2002. Basically it was a business phone, it replaced Nokia 6210, 6150 and 6110. Accessories are almost same, like a battery can work in almost all of these models. 
This phone is still popular due to its long battery time. This phone has java and LCD screen.
Codes for Nokia 6310/6310i :
* # 06 # – (IMEI) shows the serial number of your phone
* # 0000 # – version ask ki
* # 92702689 # [= * # war0anty #] – the secret menu
* 3370 # – Activate EFR
* # 3370 # – deactivate EFR
* 4720 # – Activate HR
* # 4720 # – off HR
* # 746025625 # (* # sim0clock #) – SIM Clock Stop
