Download iOS 9.3.4 (13G35) 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 9.3.4
Release Date 2016-08-04
Update Date 2016-08-01
Sha1sum
8989675f4f446ed3dc928299837c3caf23880574
Sha256sum
a8a5dca9d6a077bfb0c7270b2c416d9596245773151b22a898ecc1637d9256a9
md5sum
88e6d7f0c356799a312ce06eee3e071b
Size 2.05 GB
FileName
iPhone8,1_9.3.4_13G35_Restore.ipsw
Status

Download IPSW (2.05GB) Check device info
Release Notes

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

iOS 9.3.4 provides an important security update for your iPhone or iPad and is recommended for all users.

For information on the security content of Apple software updates, please visit this website:

https://support.apple.com/kb/HT201222