Electrical connector caps, plugs and covers are designed to provide mechanical protection for electrical connectors. They are available in many shapes and sizes to accommodate different types of electrical connections. For example, covers for D-subminiature connectors are shaped like the letter D while covers for Bayonet Neill Concelman (BNC) connectors are round. Typically, caps have male threads and plugs have female threads. Caps fit over the ends of electrical connectors, enclosing the pins and contacts as well as the mating surface. Plugs fit inside the ends of electrical connectors, enclosing the pins or contacts but leaving the mating surface exposed. Some electrical connector caps, plugs and covers are designed to dissipate electrostatic charges. Others provide an electrical shield. Common types of electrical connector caps, plugs and covers include devices for D-subminiature socket or pin connectors with 9, 15, 25, 37, or 50 contacts. Covers for 50-pin and 68-pin small computer system interface (SCSI) electrical connectors are also available.