Comprising a heavy-gauge copper outer vessel with an internal perforated shelf for copper sulphate crystals, a porous pot and an amalgamated zinc rod fitted with a wooden supporting cap. The zinc rod and copper vessel are each provided with a 4 mm. socketed terminal. In this cell E = 1.08 V approx. Working capacity 0.85 litre Size of copper vessel : 130 x 90 mm diameter approx. Size of porous pot : 150 x 150 mm diameter approx. Size of zinc rod : 150 x 12 mm diameter approx.