What type of screw?

Shoulder screw.

Perce

Lord only knows. Some kinda hex/phillips (guessing) head washered shouldered cap screw ....ISO!. Whatever it is, probably not a standard fastener. You might find a replacement from your local small computer repair shop. Also try googling for "computer fasteners" (no quotes) and throw in "standoff" for grins.

nb

Shoulder screw.

Right column:

I could be wrong, but I think the shaft of an "axle screw" is the same diameter for it's entire length (both the threaded and unthreaded portions) while a "shoulder screw" has a wider unthreaded portion, thus the name "shoulder".

Coincidentally, I just finished using a rented power snake where the "axle screw" that holds the head on was in such bad shape that I had to use vise grips to get it out so I could put on a cutting head. They're getting it back with a extra long fully threaded bolt 'cuz that's the first thing I could find with matching threads. I'll give them back their beat up axle screw also so they don't charge me for "damaging" their equipment.

Looks like a "Dell" part.

Look for a PC screw assortment from one of the hardware outfits. They will usually sell you a bag of screws for a few bucks with a bunch of each type you find in PCs. That one is a 6-32 shoulder screw. The finer thread ones like you see in diskette drives and CDROMs are commie metric. If you only need a couple I can mail you some.

Yes it is from a Dell Optiplex745,I checked the Dell site first before I posted this message no luck. Last night I went back to work on the computer and surprize,they have four of those screws on the dummy cover for the disket drive,Thanks for your offer now I have enough screws.One more thing,I know it is a 6-32 thread,but what are the correct measurements?