15 kr
A chrome-plated special screw that has thread 8-32, so approx. 4.1mm coarse if you measure the diameter of the threaded part with a caliper. The maximum diameter of the skull is only 6.4mm, which is significantly smaller than a normal skull for a screw of this size. The total length is 19.5mm and it is recessed with a lumpy skull. It fits perfectly in many places because it is chromed and has the undersized skull.
If you want to shorten the screw, thread on an 8-32 nut before cutting the screw, then unthread the nut and clean the threads at the cut. Keep in mind that it is a countersunk screw so be careful not to push cracks in the lamp glass, plastic and other sensitive parts. It is easy to pull too hard and damage the things you have to screw. Check the picture how to measure the length of a screw with a countersunk head.
The difference between UNC and UNF is the number of threads per inch.
UNF is fine-threaded with more threads per inch than the coarse-threaded UNC thread.
The smaller sizes are divided from 0 to 12 and are called numerical threads
The larger sizes start with 1/4″ and so on.
