Review on Stant 10504Y Flex Fuel Locking by Peter Green

I bought a used Flex Fuel Suburban with a black keyless cap. Luckily I was able to remove the cap when filling up without a key (the key didn't come with the Suburban when I bought it). I wanted a yellow cap (which accurately identifies the flex fuel engine) so I got the Stant. The only small caveat I have is that you MUST lock the lid to remove the key. The key can only be removed when the cover is locked. In the rare event that you can lose your keyring (with the Stant key attached) you're screwed if you don't have a spare key readily available. You'll need to keep a spare key in the glove box if you ever want to fill up on that occasion. In my opinion there should be a position where you can remove the key and leave the cap unlocked, leaving it locked or unlocked at your discretion. Other caps work like this. Minor but I would give it 5 stars if you could keep it unlocked.