HHumR

is the gas cap for '06 hhr vented/ non-vented any known brand of locking gas cap for '06 hhr?

EinST

No, it's not vented. Check out CST 5903. The thing is, it's going to be weird if you're used to Stant. You insert the key, unlock, and then remove the cap from the filler neck. After you're done, you install the cap onto the filler neck and then lock the cap with the key.