The MIL-DTL-38999 Series I & II high-performance Cylindrical Connector with low-profile 3-point bayonet coupling. It is designed for cable-to-panel I/O applications in military aerospace and other demanding situations. Environmental class plugs and receptacles with high-density insert arrangements - are available with crimp removable contacts, PC tails and solder cups. Glenair manufactures a wide range of environmental class MIL-DTL-38999 type connector including lanyard-release products, composite and specialty metal cable plugs and receptacles and coax contact equipped products. It is also designed for use in pressurized or severe environmental applications. Hermeticity is generally defined as the state or condition of being air or gas tight. In interconnect in dielectric breakdown, corrosion and loss of insulation resistance between conductors. The classic hermetic application is a receptacle feed-through penetrating a pressurized bulkhead or pressurized equipment housing.