Iphone model MC143C unlock

You can Unlock the Phone and then Jailbreak it ......I will Clear the jailbreaking and Unlocking process...

Jailbreaking is important,Because without jailbreaking the Phone you cannot able install the third, party application ,you cannot connect to IOS ....So jailbreaking important,you can unlock then jailbreak the Phone...But unlocking is to remove the Network lock,,then only you can use any GSM Network Sim Card in the I-Phones,You cannot use CDMA Network in the Unlocked Phone,only GSM Network locked Phones can be unlocked,CDMA Network locked Phones cannot be Unlocked....Without unlocking you cannot use other Network Sim card,So unlocking is important,
You can Unlock the I-Phone 3GS using the remote I-Phone Unlock service,to get the remote I-Phone Unlock service you can reach the site Simpleunlocking.com and get the service and Unlock it...You need to install the I-tunes latest version in your apple i-phone 3GS to use that remote Unlock service.......All Network locked I-Phones cannot be Unlocked.So check service for Your Network locked Country,Network...then order service and Unlock it.(If you need to use Other Network than T-Mobile means You can unlock it)...