213868-1 is a reverse sex square flange receptacle assembly designed for AMP Circular Plastic Connectors, Series 1, in a 23-19 arrangement configuration. This receptacle accepts posted socket contacts and features mounting holes for panel installation with a maximum panel thickness of 0.125 inches (3.18 mm). The connector housing is constructed from thermoplastic material rated UL 94V-0, black color, and operates reliably over a temperature range of -40°C to +105°C. It incorporates molded-in keying in a 4-key optional configuration (Style B) to prevent mismatching of standard and reverse sex connectors, and includes built-in pin and socket protection with polarization for proper mating. This connector is ideal for commercial signal and power applications requiring secure, quick connect/disconnect capability with thread-assist positive detent coupling.