The Reed GU-3001 is a handheld meter for measuring AC and DC magnetic fields in milliGauss or microTesla using a uniaxial Hall effect sensor. It offers a north/south pole indicator, data hold with max/min tracking, zero adjustment for relative readings, and an LCD display, and can mount on a tripod for extended monitoring sessions. It measures roughly -3000 to 3000 mG (or -300 to 300 uT) with a 40 Hz-10 kHz frequency response, and runs on six AAA batteries or an optional AC adapter.