Problem:

No Signal or weak signal on your iPhone 4

Have a weak signal or low bars

Solution:

Replace Blue Inductor Coil

Details:

-This is a blue Antenna coil which connect and amplify the current from your antenna.

-This coil fixes GSM signal faults.

-Issues are caused when the antenna coil is broken or burnt out on the logic board is burnt out.

-This is the same part specification as the part Apple.