Download iOS 9.2.1 (13D15) for iPhone 6s

You will have to note that you can only restore signed IPSW firmware files using iTunes or 3utools.

❌ This IPSW firmware is not being Signed by Apple

Firmware Identifier iPhone8,1
iOS Version 9.2.1
Release Date 2016-01-19
Update Date 2016-01-12
Sha1sum
251bce82c833ed053176faade41e5adfa5c2c65a
Sha256sum
aa75ad2b5db958eb29be2fb89c8f1053c86d85ced147144d1319c738ea37cb4d
md5sum
fb86ad6278b1cf5dbecf0ef82f51e1dc
Size 2.00 GB
FileName
iPhone8,1_9.2.1_13D15_Restore.ipsw
Status

Download IPSW (2.00GB) Check device info
Release Notes

It should be noted that these are the official release notes for the from Apple

This update contains security updates and bug fixes including a fix for an issue that could prevent the completion of app installation when using an MDM server.

For information on the security content of this update, please visit this website:

https://support.apple.com/HT201222