Greisinger gmh 175 precision thermometer greisinger gmh 175 p the greisinger gmh 175 is a precision thermometer that can measure liquids air and gases the gmh 175 brings laboratory level performance in a portable handheld instrument battery life is typically 200 operating hours from a 9v pp3 battery supplied a dc connector is also supplied for an external 10 5 12v direct voltage supply the large 3 frac12 digit display is easy to read p p what s in the box br greisinger mh 175 br