

Interesting technique, Al--I'll have to remember that one.
I found this specimen in an antique store in Gloucester today. Although technically not a double box end (one end is 1/2" square for a ratchet driver), I'm including it anyway because both ends are in fact boxed.
Snap-on S-8164, 5/8" 12-pt x 1/2" square, dated 1947
This is a specialty wrench, often described as being for head bolts, but CollectingSnapon describes it as for starter or distributor bolts. Anyone know?
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There must be something about a particular application that drive this design--otherwise why not just use a deep well socket on an extension? Maybe it was a nut on a long threaded shaft, too long for a deep socket...That Snap On is a torque adapter. The square drive is directly over the 12-pt. end so you get an accurate reading on the torque.
It is also useful for starters which have little clearance around the starter, and the mounting bolt circle is smaller than the starter body.
To expand on Outlaw's post, imagine a starter that has a mounting flange where the fasteners are located in a recess that is smaller than the main body of the starter motor. You can only get to the nuts/bolts from the side, since the body of the motor blocks access with a socket and extension. You could use an open-end or box-end wrench if there are no other obstructions, but since the engine block is in the way for over half the diameter, you need a tool that can reach around the starter motor and get into the recess where the nuts are.
Now put a square drive directly over the box end at the far end of the beam of the wrench, and you have the type of tool you show.
In practice, that tool is properly used to torque bolts (it is the proper size for 7/16" SAE hex head bolts) where there is an obstruction (such as a rocker arm) that prevents use of a standard socket and extension.
I have some of those Snap On torque adapters. The big one on top is a S-8666 for 1949-1953 Ford engines, it goes around certain engine compartment obstructions to get to some of the head bolts. The next one is a B4203 for Case and Minneapolis tractors, then a S8684B for John Deere and Oliver. Last is a S-8659 for a Ford oil pressure sending unit, notice it is an open end.
If it is in line, it is a torque adapter. If the square drive is offset, it is a multiplier to the extent that it adds length to the arm of the torque wrench. A true torque multipler is a gear reduction and reaction bar that greatly reduces the effort applied to the input in order to get the desired torque applied to the output.

If it is in line, it is a torque adapter. If the square drive is offset, it is a multiplier to the extent that it adds length to the arm of the torque wrench. A true torque multipler is a gear reduction and reaction bar that greatly reduces the effort applied to the input in order to get the desired torque applied to the output.
Here's a handful of Bonney torque multipliers/adaptors that I picked up last year and previously posted in the 'Bonney Affliction' thread. Some are engraved GE, presumably GE aircraft which is relatively close to me.
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Interesting!
How does that one at the top of the photo work? Looks like it has both an open end and a socket.![]()
















That Mossberg set is beyond awesome.

That Mossberg set is beyond awesome.

PM sent!LesserSon will be wanting one of these as well.
I guess I'll volunteer to be the guy who follows that which cannot be topped. Nice Mossbergs! .....Plomb 1164, 1 5/8" x 1 11/16"
Brian
WarrenJ,BB How do you organize all your DBE in a drawer or do you hag them on peg board Looking for some drawer ideas. Thanks



BB thanks, I knew you had a large collection and wondered how you did it.