The Extech EX530-NIST is ruggedly designed and waterproof to IP67 standards, and is ideal for use in the outdoors, on boats, and in any harsh industrial environment. It has a double molded housing and is drop-proof up to six feet with a safety rating of CAT IV 600 Volt and CAT III 1000 Volt. It measures AC/DC voltage and current, resistance, capacitance, electronic and electrical frequency, temperature, 4 to 20 mA, and duty cycle. Additional features include: 0.06% basic accuracy, continuity beeper, diode test (2.8 Volt open circuit voltage), 40000 count resolutions, backlit LCD with barograph, peak hold, min/max, relative mode, data hold and 1000 Volt input protection for all functions. It includes NIST Certification.