MARK SYKES / SCIENCE PHOTO LIBRARY MARK SYKES / SCIENCE PHOTO LIBRARY
Thermostat. Interior of a temperature sensitive thermostat showing the bi-metallic strip (strip of metal, centre left). The bi-metalic strip contains two metals that expand at different rates on heating. The strip bends one way as the room gets warmer, switching off the system in the process, and bends the other way as it cools to switch the system on.
Model release not required. Property release not required.