iPhone iOS Firmware iPhone ipsw firmware download that provided by Apple, when you do the relevant operation at your own risk.

IPHONE 6S PLUS 11.2.1

IPHONE_5.5_11.2.1_15C153_RESTORE.IPSW
Categories:
11.2.1
Version:
2.61 GB
Size:
December 11, 2017
Date:
Unsigned
Status:
The file can help you a lot ?