HD Series Subminiature Connectors The Hirose Connector D sub plug is part of the HD series of subminiature D sub connectors. The Hirose HD series are a compact and sturdy connector due to a metal shell and glass filled resin insulator, offering resistance to heat and chemicals. Hirose offer D sub connectors in a variety of contact variations. Each Hirose Connector D sub plug features stamped contacts for easy soldering to a variety of stranded single core cables. Typical uses for the Hirose Connector D sub plug include use as an interface in computers, control equipment, radio equipment and measuring instruments.