What are these Cman drivers?

[mtnwkr]

Found these at a swap meet this afternoon. Two sets of four, no idea what they are for and don't need them, but the price was right. Anybody have any ideas?
Edit..
Ahh.. Clutch head drivers.
I don't have a use and would be willing to trade for a set of Cman nut drivers.

 

[eborcim]

My guess would be two versions of clutch head drivers.

 

[metaldad]

Tamper resistant clutch fasteners.
half way down the page:
http://en.wikipedia.org/wiki/Clutch_head#Clutch

 

[Standardbyke22]

I believe those are security drivers for those screws that you can only tighten and have to cut off to remove. One place you might see those screws are in store bathrooms that have stall dividers on the door hinges and wall brackets

 

[Jim C.]

They're clutch head drivers. They were used occasionally on old cars from the 1950s and 1960s, but more commonly on old camper trailers and motor homes. If you'd like to sell them, or trade for them, send me a PM. Thanks.

Jim C.

 

[wafrederick]

The clutch head bits and screwdrivers are getting hard to find these days.Matco used make a bit or two,have been discontinued and can't get them anymore.

 

[scaron]

wow i had no idea that craftsman ever made a clutch head set. neato! cool find; even if you'll likely never use them, one can never have too many different kinds of drivers fwiw these are a bit different than the "one way" head that you'll usually see in restroom stall dividers.

 

[Jim C.]

The clutch head bits and screwdrivers are getting hard to find these days.Matco used make a bit or two,have been discontinued and can't get them anymore.

I think that's because they're not really used too much any more. They're more commonly found on older (pre-1970) vehicles, and those were mostly RVs and campers. At least that's been my experience with them. I have a few older Craftsman clutch head sockets with the =V= manufacturer's mark on them. They're 1/4" drive, in sizes 5/16", 1/4", and 5/32".

Jim C.

 

[tomshep]

Holley carbs use a clutch head screw in the back bowl.

Tom

 

[WWIIjeep]

Along with being popular on certain older vehicles and in the motor home industry, clutch head screws were used on some electronics and electrical equipment in the 60s and 70s. They're not really tamperproof, because in a pinch, you can usually turn the larger sizes with a regular flat-blade screwdriver.