The DUOYI Digital Earth Tester is a professional electrical testing instrument designed to measure earth (ground) resistance and earth voltage in electrical installations. It helps electricians, maintenance engineers, and technicians verify the effectiveness and safety of grounding systems in residential, commercial, and industrial environments. The tester features a large digital LCD display for clear readings, a rotary function selector for easy operation, and a data hold function for convenient measurement recording. It is supplied with test leads and earth spikes for accurate field testing. Its rugged, portable design makes it suitable for on-site inspections and routine maintenance.