This series of electrical connectors features: removable crimped contacts (except for sintered sealed contacts), anti-misalignment design; multiple mounting options for the socket (box type, wall mount, front-mount, rear-mount, and nut mount, etc.); can be equipped with standardized tail connectors; the insertion surface uses an interface seal, and the tail uses a wire seal, providing excellent environmental resistance; five-key positioning with a guiding function, and five key replacement methods (three for size 9 housings) to prevent incorrect insertion. This series of electrical connectors also features: bayonet-type quick connection and disconnection; small size, light weight, and short housing; removable contacts, including crimped and soldered types (except for sealed contacts); excellent EMI/RFI shielding performance; five-key positioning to prevent incorrect insertion; and lightweight design, suitable for environments without high-intensity vibration or wind and sand erosion.