MTFCA Forum

I picked up these large valve brass Schrader valve caps at an estate sale. They are all stamped "Schrader U.S.A."

The inner diameter is 9/16" or approximately 14mm.

Standard Schrader caps are shown for comparison.

Can anybody tell me what the applications were for these? Automobile, truck, airplane, military or non-tire/inner tube related, etc.?

There were also a number of WWII era military items at this sale (I also bought a WWII era military/jeep tire pump) so maybe these caps have something to do with a military vehicle?

I'm usually pretty good with Google to find answers but these have me stumped.

Thank you.

I have never seen those in a car or truck application. I found this on Wikipedia; "Schrader valves of varying diameters are used on many refrigeration and air conditioning systems....by plumbers conducting leak-down pressure tests....some fuel injected engines....SCUBA systems".
I couldn't find pictures yet.
Rich

For what it's worth.

They are probably for some non-automotive application like HVAC or refrigeration or practically anything involving a compressed gas.

However, the brass caps are even a larger diameter than the oversize stem ands caps on the compressor for my central air conditioner system. Same goes for my 2003 Pontiac air conditioner.

Years ago I picked up a bunch these for a buck at an estate sale of a guy who, I believe, worked in HVAC. However, they are standard size. I bought them merely for the new valve cores as well as the nickel plated caps which are period appropriate for antique cars and they are also "added insurance" because the rubber seal inside the cap completely seals the mouth of the valve.