Size width 64 mm height 50 mm depth 30mm.

The Receiver Pack Tester is a hand held expanded scale voltage indicator covering the range 4.3v to 5.2v (4 cells) and 5.5v to 6.4v (5 cells) battery cell size is selected by a slide switch. Dual load rates are used 120/140mA push switch not pressed and 480/530mA when push switch is operated. Connections are via screw block connectors. This unit should only be connected to the battery directly or through the switch harness charging lead.
The unit is designed to indicate the safe, marginal and unsafe operating areas of receiver supply voltages.

Data Sheet