DET 20 is a conventional 3 ½ digits LCD designed to measure earth resistance, soil resistivity & earth voltage. It has a unique RSR technology in which the measurement reading remains constant even when the battery voltage drops. DET 20 has a 128Hz test frequency that eliminates the harmonics interference and has a rechargeable long-life battery which reduces costs. Earth resistance is measured by three wires & soil resistivity is measured by four-wire measurement techniques. This meter is shockproof and dustproof and comes with an ABS casing for heavy duty application. DET 20 is type tested as per IS 9223.