CC Clue (Updated)

I don’t see a CC Clue scheduled for this evening, so I thought this might make a good one… it’ll either be really easy, or maybe not… How well do you know your gas caps?

UPDATED – no-one’s even in the ball park yet, so I think maybe I cropped too tightly. See if this wider view helps any…

The usual Clue Rules apply – guess all you want, but no “confirming photos,” and try to hold your certitude to a minimum so you can enjoy everyone else’s guesses, too.