2 ways to check the status of SHSH2 Blobs
Knowing the status of SHSH2 blobs is very important if you plan to upgrade or roll back to a version that no longer subscribes. This will help avoid problems already during the process itself using futurerestore.
If you saved .shsh2 blob with tsssaver .1 conan . com  or tsschecker, then the compatibility of the files with some models should be checked. In mid-February 2017 a bug appeared that made some blob files useless.
Before that, you need to know the configuration of the board of your device. It can be found in the Battery Memory System Status Monitor application. Open the application, go to the System tab and see the model of your device.
As an example, we will use Windows and check the compatibility of iPhone 5s GSM with iOS 10.3.3 blob. The same can be done on a Mac or Linux.

A simple way to check the status of SHSH 2 Blobs

Step 2:  Select your .shsh2 file.
If you have several files saved, it's best to select the latest one, but you can check everything, and then delete unnecessary ones.
Step 3:  Select the device model and iOS version of your blob and click Submit.
Step 4:  If the board configuration matches your device, your SHSH2 file will work. You can use this .shsh2 blob in futurerestore to update or rollback.

Advanced way to check the status of SHSH 2 Blobs

This method is suitable for those who used to save TSSCHECKER files.
Before you start the process, you must have the following files:
Step 1:  Create a folder on the hard disk (for example, D: img4tool) and copy the contents of the img4tool-latest.zip archive there.
Step 2:  Copy the .shsh2 file to the img4tool folder. You can rename your .shsh2 file to "my.shsh2" to make it more convenient.
Step 3:  Open the .ipsw file with 7zip or a similar program and copy BuildManifest.plist to the img4tool folder.
Step 4:  Open a command prompt, locate the img4tool folder, and enter the following command:
img4tool_windows -v BuildManifest.plist -s my.shsh2
If you see 3 [OK], and DeviceClass matches the model of your device, the .shsh2 file will work. You can read our instructions on how to roll back to a non-signed version of the firmware.
Note: As an example, we checked the status of the iOS 10.3.3 file, but before iOS 10 it is no longer possible to roll back if you do not have a special BuildManifest file for the Apple A7 processor.