I picked up what I thought was a Snap On 1/4" drive extension at a yard sale for 10 cents. Figured I got a killer deal. The extension is black and marked M2 in addition to Snap On and USA. The female end is a bit loose on a ratchet but I attributed it to wear. BUT a socket won't fit on the male end. Measuring the male end indicates 0.277" and the female end reads 0.283" These measurements cross to about 7mm. Could the M2 mean metric? I searched here and on the Garage Journal with no luck. Anyone ever heard of 7mm square drives? Mods, if this question shouldn't be posted here please delete.
Did you look for information on Snap-On's site? I'd imagine they sell tools world-wide and would use metric sizing in other places.
almost looks like it may be for aircraft or miitary use?,i bought some torx bits like that once,they wouldnt fit anything i had,were either too big or too small,they were the black coating like your extension.
What you have is a 9/32" drive. They were sold to the military during WWII. The idea was to keep the GIs from building up a tool set at the expense of the Government. Thus the 'M' marking. The shape of the 'S' can narrow down the date. Better send it to me so I can dispose of it properly.
I have a 3/8" drive Snap On extension with a strange size male end...A hardware guy told me it's a 'special tool' for a metric pipe plug. Male end measures 12 mm. It's chrome plated, like my sets. Female (driving) end is std. 3/8", I was surprised at its weird 12 mm. sizing, because it has the locking ball on the metric end. (so it will hold the plug for starting, obviously)
nearly the same thing happened to me bought a snap on extension at a yard sale cheap . got home did not fit anything found out it was 5/8 drive
Thanks. After the 9/32" info provided by @GearheadsQCE I was able to find info about 9/32" drives. Learn something new daily here on the HAMB.
Funny how they make “special” sized or marked stuff, then later on it gets sold off in bulk. I have stuff marked as property of the Japanese emperor, won’t be getting them back.
Don't know much about military Snap On stuff but when the local Snap On dealer repaired a 3/8" stubby yard sale ratchet he was able to tell it was from 1969 and not military. He said if it was a military ratchet he couldn't repair it. No idea why but he made my 50 cent ratchet work like new.
The website Squirrel posted is really cool. There are people really into this kinda stuff. I'm not a big collector but have a few WW2 ratchets and sockets. But honestly I just enjoy using the tools and frequenly remark to myself how they get me out of a jam on a stripped fastener or something hard to reach..
Well, you learn something new every day. I worked for Snap-on for over 20 years and never knew that the 9/32" midgets were standard fare before the switch to 1/4". Thanx for the link @squirrel.
Bottom line is that this extension is of no use to me and really not worth enough to justify the hassle of posting it on the auction site. That said, if anyone here on the HAMB wants it they can have it for the cost of postage. PM me if interested.
I've got an old 1/2 snap on rachet some where. Had it since the early 80's. Back then snap on man said it was a military contract but he fixed it no problem. Probably ought to look for it...
European (France, Spain, Germany) manufacturers have used metric for a loooong time but - strangely - their socket sets use 1/2, 3/8 and 1/4 inch dimensions on ratchets, pull handles, extensions and the drive end of sockets. Go figure!
I have a set of those! I had to move them to a different drawer, to stop myself trying to mix them with 1/4" stuff.
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