Abstract: A meter is provided for measuring the total parts per million dissolved solids in an electrolytic solution. The sensor for the meter is located on an upright probe on the face of a mount which is rotatably attached to the casing of the meter. Such a construction enables the sensor to be immersed directly into a batch of the solution while the casing is maintained in an upright position to enable the scale on the upper surface thereof to be viewed by the operator. In addition, a recessed circular opening is provided on the face of the mount about the upright probe to enable the threaded ends of sample bottles to be attached thereto.