Screw head?

Can anyone tell me what this type of screw is called?
http://www.geocities.com/ceh383/screw.jpg
And, where can I get tools to fit it......

Looks like the one's used on the old chebbies, Snap-on has a bit to fit it. Maybe Craftsman, too...?

Yep, you are correct....it's on a 51 chevy. Couldn't find a Craftsman bit to fit it. Snap On probably have one, but at this point I have no access to the Snap On man. I was wondering what it was called so I might be able to find tools on-line.

Thanks Denny, I'll see what I can find.....

Mobile home manufacturers used this type screw to attach the aluminum outer panels to the framework.

For the record, I believe that's called a clutch head screw.

They come in 3 sizes!!

A flat screwdriver of just the right size will work in a pinch.
John Deere used them in the 50's to hold the tin on.

Thanks for the input!!!
Found them on McMaster-Carr, 5 sizes in all (3/32, 1/8, 5/32, 3/16, 1/4) I probably don't need them all but I ordered them all anyway.....After all, I want to reuse the screws.....