A quick google shows that you have a 1940s US made Plomb "Wright Field" 9/32" drive flex handle. There is an article on them here Alloy Artifacts

I wonder if the arrow is the US military's equivalent of our "crow's foot"?

Brian

Edit:  Snap-on also made 9/16 tools https://www.collectingsnapon.com/index.php?page=socket_sets/C9-32inch/9-32%20intro

Edited By Brian G on 18/06/2019 09:16:49

Hopper, YOU AINT SEEN NOTHING YET !!

No matter what the question, someone here has the answer.

I’m still surprised the French don’t use 10mm and 15mm drives!

Hi

Some where I have a set bought from Wistons many years a go, Interestingly this had an od 1/4 drive socket in it that fitted Meccano square nuts.

Strong bar or flexible handle? On reflection perhaps the former name (new to me) is a better one.

I wouldn't call anything less than 2ft long a breaker bar but I see Snapon call a mere 15inch one thus. I would call it a swivel joint handle.

Supposed to be cadmium plated according to the link.

Yours looks like the plating has been stripped to bares steel. I hope the seller remains in good health…

Neil

I used to remove / refit the sump plugs on our Renault cars using a 3/8 square ratchet and extension, It was a slightly loose fit in the 10 mm square socket of the plug, but worked without problems.

Possibly the Continentals have their own standards for socket drives, (although they use BSP threads on water fittings, calling them "Gas" )

Or a similar strategy to that of Ford in needing a 7 mm Allen key for the calliper retaining bolts on some models?

Bosch used a triangular head on the plugs retaining the governor shaft on the EPVE injection pump. Guess the only place where you buy an expensive triangular socket?

Similarly, Japanese manufacturers of "cassette" injection pumps used five sided heads on their retaining bolts!

Howard