T3403400U is a circular DIN connector from Amphenol's signalmate® C091 (M16 Size) family of industrial connectors. The connector is part of a modular series available in multiple configurations (M16 A, M16 B, M16 D, M16 D+, and M16 Q variants) with various coupling systems including threaded, bayonet, and quicklock options. While specific technical parameters for the T3403400U variant are not explicitly detailed in the available documentation, the C091 family offers environmental protection up to IP69K when mated, operates across temperature ranges from -40°C to +100°C, and provides excellent EMI shielding capability. These connectors are designed for diverse applications including 4G/5G mobile radio networks, measuring instruments, and equipment requiring reliable power and signal connections in demanding industrial environments.