JDSU TestifierPRO TP655. Operating voltage: 9 V. Dimensions (WxDxH): 33 x 67 x 168 mm, Weight: 235.3 g. Operating temperature range (T-T): 0 - 50 °C, Operating relative humidity range: 10 - 90 %, Storage temperature range (T-T): -10 - 60 °C