For demonstration of Ohm's law, according to which V/I = constant (R) by E.S.A.W. When connected to an external battery through a pair of color coded terminals with a suitable resistance connected across another pair of terminals, the voltmeter and milliammeter readings are available on switch ON the supply. Current flowing through the circuit can be controlled through a rheostat knob. With milliammeter 0-600mA DC, voltmeter 0-6V DC, rheostat knob, push key, and 4mm socket terminals mounted on top of plastic moulded enclosure. Circuit diagram indicating all components printed on top of the enclosure. External battery and resistances not supplied, available optionally.