Some kind of serpentine belt tool?Better image of nicer tool.
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Better image of nicer tool.
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Better image of nicer tool.
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I like those Fisherman's Pliers rubicon, most of the ones you see are rusty from use but yours look to be in real nice shape.
Got these sockets over the weekend
5206-W, 3/16 Whitworth
5210-BS, 5/16 BS - 1/4 W
5212-BS, 3/8 BS - 5/16 W
5212-W, 3/8 Whitworth
5421, 21/32"
All shallow 12 pt sockets, Whitworth are 3/8 and 21/32 is 1/2. All Proto Mfd USA, all have single detent with asterisk except 5210-BS which has one detent hole drilled in the socket.
A couple recently found Proto Los Angeles 1/2" drive sockets and an interesting (to me) 1/2" drive 9/16" 5418-H with a "-77" stenciled right after the 9/16. The stenciling looks factory and not like any PO marks I've ever seen. Anyone familiar with this mark?
That looks more like a Pi symbol than a 77. But that might just be me.

That looks more like a Pi symbol than a 77. But that might just be me.
Aaron is correct, that's a Pi symbol. I posted the MAC/PROTO date code sheet (post 1975) here, which does include alpha, beta & gamma, but no Pi. That said, my bet is it refers to a production location.
Aaron is correct, that's a Pi symbol. I posted the MAC/PROTO date code sheet (post 1975) here, which does include alpha, beta & gamma, but no Pi. That said, my bet is it refers to a production location.
Came across these in my dad's old tools, brought them home. Someone suggested I post them here to learn more about them.
Any information on these?
Proto 12 pt line wrenches. Marked "MFD Los Angeles USA"
Its not often someone bought that whole set, so if that's how it was bought by your dad, then WOW. Very cool, not often to see a completed set like that.
If it says Proto Los Angeles, it is generally accepted that they were forged between 1951(?)-1957.