GRAIN MOISTURE METER Solid state, electrical resistance type sensor provides accurate readings from 0 to 200 centibars, covering the entire soil moisture range required in irrigated agriculture! In operation, soil moisture is constantly being absorbed or released from sensor. As soil dries out, sensor moisture is reduced and electrical resistance between electrodes is increased. Resistance is read by the hand-held Watermark digital meter ( sold separately below) which gives a digital readout in centibars of soil water suction. Digital meter features soil temperature compensation which adjusts for the effect soil temperature has on electrical resistance reading. Temperature scale can be adjusted to use either ° F or ° C scales. To use, bury sensor to desired depth, connect alligator clips located on meter to the sensor, and view results on digital display. Sensor is manufactured from non-corrosive parts and measures 7/ 8 " D x 2 " L. Meter can read an unlimited number of Watermark Sensors. Accuracy: ± 3% . Dimensions: 3-3/ 4 " W x 5-3/ 4 " H.