The Simmerstat provides infinitely variable control of the heat output of electric hotplates, boiling rings, grills, Grill – boilers, warming cupboards etc. Its smooth action allows any heat from zero to full to be selected at the turn of a simple control. The simmerstat cuts down electricity consumption by up to 50%. No special allowance for fitting are necessary as it occupies the same space and utilizes the same fixing holes as ordinary three-heat switch and wiring is simplified.