No brakes in the morning. It will definitely wake you up more than coffee.

[WyrTwister]

Amazon.com: ACDelco 176-1332 GM Original Equipment Power Brake Booster Vacuum Hose with Clips and Check Valve: Automotive

This says it has a check valve and I think it is the same part # in your photos !

I think you can verify that by trying to blow through the hose . If it passes air , try blowing in the other end of the hose ?

God bless
Wyr

PS Check the 2nd consumer review .