Circular connectors, featuring high shielding, precision pins, multi-level sealing, and reliable mating and unmating, are widely used in various types of measurement and testing equipment. They connect sensors, data acquisition modules, test probes, and control units, reliably transmitting weak analog signals, high-frequency test data, and power while resisting on-site electromagnetic interference, dust, and moisture. This ensures precise and undistorted measurement data, making them suitable for applications such as laboratory testing, industrial online monitoring, and outdoor field testing.