Description: 100% Brand new and high quality Perfect for fun learning. Comes with everything needed to experiment with green energy. 1 set includes digital clock, zinc/copper plates, wires etc. You can experiment with different fruit like lemon, orange, tomato etc. The fun is unlimited. Type: Kids Bio Energy Science Kit Material: Plastic, metal parts, electronic components Cable length: approx 15cm Zinc/copper plates size: approx 1*4cm Ages: 7+ years Package includes: 1 Set Kids Bio Energy Science Kit How It Works: 1. The metal strips and fruit make a simple battery that creates electricity to operate the clock. Each fruit works as a device called an electrochemical cell. It converts the chemical energy stored in the metal strips into electrical energy. Four or two fruits are needed to make electricity strong enough to operate the clock. 2. A cell works because of the chemical properties of the metals inside (in this case copper and zinc). The different properties cause tiny particles charged with electricity. (called ions) to move between the two metal strips. This flow is an electric current. The fruits contain the particles that allow the current to flow, but it stops the metals from touching. Electric current also flows along the wires between the zinc and copper strips and the clock. This current makes the clock work. Note: * Due to the light and screen difference, the item's color may be slightly different from the pictures. * Please allow 0.5-1cm differences due to manual measurement.