How to restore your iPhone, iPad or iPod back to default firmware

If you had jailbreak your i device such as iPhone, iPad or iPod, and you wish to restore them back to current iOS 4.3.3 (17 July 2011), you may download to the list as below,

Then follow the step as below.
1. Connect your device to iTunes.
2. Hold Shift(Alt for Mac) button,  and click on the Restore button in iTunes.
3. Browse to the IPSW file and perform the restoration.