Directly hunt cat5e, cat6, telephone wire, coaxial cable, usb cable and other cables. 'blink function', for locating network port by flashing the port light on hub / switch. Check wiring error in cat5e, cat6, or coaxial cable, such as open circuit, short circuit , jumper wire, reverse connection. Locate the wiring or connection error. Measure cable length up to 1000m and locate the breakage point. Polarity test function measures dc voltage (0.5-60 v) memory and storage for calibration data.