Abstract: A flowmeter head is in the form of side-by-side channels of non-magnetic, electrically insulating material with the channels of very similar size. Sufficient precision of channel size is attained by boring the channels or by using drawn tube of closely controlled size. A radial electrode is provided in each channel, e.g. by drilling a fine hole in the channel wall and sealing a wire in. The electrode arrangement permits an applied magnetic flux to pass through first one channel, then the other. Earth electrodes are provided at the ends of each channel. An earth-loop free connection to a differential amplifier of a flowmeter apparatus is possible with the electrode configuration. The precision of the channel size improves common-mode accuracy and the earth-loop free connection reduces drift and noise.