Sper Scientific 840045 EMF Meter Sper Scientific 840045 EMF Meter Reads milli-Gauss and micro-Tesla on a large 1" high display. The EMF Meter's display indicates when the object being measured is out of range as well as when the battery is low. Frequency (band): 30 to 300Hz Sampling Time: 2.5 times per second Reads milli-Gauss and micro-Tesla Accuracy: 2.5% + 3d