The model HT321 represents the basic instrument of the new family 320 multimeters, which also includes the tools HT322, HT326 and HT327, designed in accordance with the criteria of the measurement category CAT IV 600V and therefore suitable to operate also in close proximity to a source of power which is required a high standard of safety. The HT321 run primarily measures AC and DC Voltage up to 600V with complementary functions of Resistance, Test continuity and Test Diodes. The tool is designed in accordance with the safety regulations EN61010-1 protection Class 2 (double insulation). The multimeter HT321 is equipped with a large LCD display and each function can be selected via a switch with 6 positions. Additional functions provided are the measure of the values MAX of every size, the HOLD function for the maintenance of data display and the ability to insert the manual transmission, of course. The instrument has the function of Auto Power OFF after 15 minutes of non-use to preserve its internal battery.