The MS3102E20-29S is a 17-position military standard Box Mounting Receptacle with socket type silver-plated copper contacts and 20-29 insert arrangement. Shell components are fabricated from high grade aluminum alloy. The standard hardware plating is electrically conductive cadmium-plated finish with an olive drab chromate after-treatment for corrosion resistance. Resilient neoprene inserts provide an outstanding moisture barrier, high dielectric strength and resistance to vibration. This connector represents well-proven electrical capability at an acceptable cost for most equipment where durability is important. The MIL-C-5015 series circular connector is recommended for conditions where vibration, moisture, pressure and temperature are extreme.