A 12V halogen bulb is mounted below metallic strip fixed on plastic base of size: 13 x 8 x 3 cm.

Consist in Bimetallic strip on base of size 130 x 80 x 30 mm A halogen bulb of 12V. is mounted below this metallic strip. The bimetallic strip is heated by glow of bulb, bends up the circuit breaks and bulb goes off. Bimetallic cools down, circuit complete, bulb glows and this whole sequence repeats.