Specialized measuring instruments for accurately measuring resistance values of electrical circuits and electronic components. Includes digital resistance meters, milliohm meters, insulation resistance testers, and ground resistance testers, used for quality inspection of electronic components in manufacturing, continuity verification of circuit boards, and maintenance inspection of electrical equipment. Unlike multimeter resistance measurement functions, these are high-precision, high-resolution specialized instruments dedicated to resistance measurement, supporting wide-range resistance value measurement from μΩ to TΩ. Essential measuring devices for quality control and safety assurance in electronic equipment manufacturing, automotive parts inspection, and power facility maintenance applications.