Product dimension (L*W*H CM): 21.8*8.4*8.7
Inner packs dimension (L*W*H CM): 22.5*9*12.8

It is used for teaching demonstration in middle school physics; it can accurately do experiments, such as: closed circuit Ohm’s law, using ammeter and voltmeter to measure electromotive force and internal resistance of battery, electromotive force and internal resistance of battery pack and output power of supply.