What screws are these?
18 gibbs 20
Machine screws. You will need to measure the length, the diameter of the shaft and the threads per inch to find exact matches.
A bit clearer picture might have brought a better answer. As blurry as it is and without a view of the head machine screws are about as close as you;re going to get. Take them to your local hardware or home store and someone will be easily able to help you determine the size.
Semi-oval head machine screws. The size and thread is the deciding information for a more exact answer.
Those are short blurry screws, probably used to hold the cover of an electical receptacle, or to hold the cover or back plate onto an electical appliance.