4-40 Jackscrews
Pairs of 4-40 thumbscrews are used to fasten certain connectors to hardware ports. The screws are typically located on either side of D-subminiature connectors such as on VGA, serial, parallel, and legacy game controller ports. They are also more recently used on DVI connectors. The typical length for a 4-40 screw used in PCs is 0.18 in.
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