Eaton must have made brass fittings at one time. I have a lot of stuff that I bought at trucking company bankruptcy auctions. I noticed just last week I have a bunch of brass 3/8 pipe plugs with an Allen head in an Eaton bag. I'm not sure that they ever sold them at retail, but these bags are not that old looking and have a hole for a pegboard hook. I have no clue where I got them.