Dell OptiPlex 7050 7060 3050 3060 and many newer mini/tiny PC (The thread is finer than those used in old models, but to our testing, no crucial difference, both screws can be used in all models). This special mounting screw play several function, fast MB to the chassis; support M.2 SSD or wifi card on the top; there is a hole in the middle to anchor another smaller screw to lock SSD or wireless card in the position.
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