Snap-On SM20.6 Flank Drive Socket

[airrj]

I found in the tool room that I am working at, a Snap-On deep well 1/2" drive 20.6 socket. I have never seen this before. I have looked in the new and a few older Snap-On catalogs as well as their online catalog and found nothing. This is a very new looking style socket not a old historical one as far as I can tell.

Does anyone know that the intended application for this is? I know that 20.6mm is basically 7/8" but I am guessing that there is a reason that they labeled it 20.6 instead.

Just a little confused.

Thanks
R.J.

 

[Moose-LandTran]

It's a spark plug socket, metric equivalent of 13/16".

 

[bgott]

Antarctica? That's down there a ways, ain't it? Are you still snowed in or is it the season where you can get planes in and out?

 

[mrshaun]

I have one on the truck now.

 

[airrj]

You have one on the truck, but is that what it is? Just a metric labeled spark plug socket???


And yep, we are flyin' planes down here now. Just starting into the summer season.

 

[MattT]

It's in the #600 (2001) catalog with all the other metric deepwells. The page doesn't list any applications for it. SM is a regular 12 point metric deepwell part # not a spark plug part #. Moose is half correct saying it's metric 13/16" though.

IIRC I've seen SM20.6 sockets on feebay as part of mil surp sets and MrShaun's route includes Ft Hood. Probably some military application.

 

[mrshaun]

only customer to ever request one was at a gmc/pontiac dealership about 6-7 years ago.

 

[djb2]

Note that the Bosch nominal dimension for sensors and plugs of that size is often 20.8mm, rather than exactly 13/16" (20.63mm) or 21mm.

 

[mrshaun]

I think it was a way to match a metric and an sae size. but no one ever really told me what it was for.