Any one know what this goes on? It fits a gas tank, but has no vent hole.

Repro gas cap - should have a small vent hole in one of the fins - most likely plugged with crud.

I have gone over this thing with a magnifying glass, inside and out. NO HOLE! soooo.... non-vented gas cap then?. Any idea what era? teens, twenties, ????

What's it made of ? Original caps of this type were "pot metal" and had a thin sheet metal baffle plate swayed into the bottom near flush with the threads, vent hole in the center of that plate, which this cap is missing. I'm not sure when this type cap was adopted but they're generally found on the mid-20s cars.

It would make a nice cap for a speedster using a lower tank and hand pump to pressurize the tank

Hi Charles,

I was told that those are radiator caps for an English Ford, such as an Anglia, 10, or some other model. I do not know, just repeating what I heard. Bill

Bill H is correct. I have such a cap made of bronze as my gas cap - I just drilled a small hole and made a round piece of aluminum that fitted in the bottom part of the cap as a splash guard, cupped it like a core plug and knocked it in place with a hammer, secured with some epoxy. A small hole in the aluminum too, and I've saved $41:50 https://www.modeltford.com/item/2901BQ.aspx

Here's the one I have - perhaps someone drilled a vent hole but it's not old & brass !

The one I have seems to be solid brass or bronze and the inside is smooth with no evidence of any baffle. Maybe the suggestion that it would be good for a speedster is the answer?

When used for an english radiator it didn't need any baffle, but when used as a gas cap it needs it - and holes. Easy to make as described above

Definitely Model Y 8hp English Ford + some later 10hp cars, until they went to pressure rad caps in the 50s.

Some also came with a script which said Enfo for English Ford. All are radiator caps for non pressurised systems.

Allan from down under.

Been using one for years on my 27. Came off an early 50's Anglia. No vent hole, never had a problem unless that why I can't get over 50mph out of the T.