Perfect for building surveys and powerlines the Digital Emf Tester With Data Logging is a compact and light device that displays readings in microTeslas (?T) or milliGauss (mG) on a triple readout 3-1/2 digit LCD. With data and peak hold capabilities this tester logs data for uploading to a PC via RS-232 and is CE and RoHS approved. Specifications Measurement Range: 0 to 2000 mG (0 to 200?T) Measurement Accuracy: ?4% + 3 digits Resolution: 0.1 mG (0.01?T) Bandwidth: 30 to 300 Hz Sampling Period: 0.4 seconds Operating Temperature: 32? to 104?F (0? to 40?C) Dimensions: 4.37 x 2.52 x 1.34 in. (111 x 64 x 34mm) Weight: 5.82 oz. (165g) Power Source: 1 ?9V? battery (included)Includes Interfacing/Data logging software RS-232 cable Battery - SKU: GTEMF1392DL