SHAON-SHANA
  the revolutionary timer

You see me in all the DIY departments.

I really don't cost much

I do not damage your refrigerator, I have been in service  for over 40 years.

If the refrigerator is off, you can open it without problem during  Shabbat.

You can bring me with you when travelling

Important! You get the control of the situation: if the temperature is too high, just turn off the refrigerator more often and for less time each time. Notice that it is not really the case with certified refrigerators. They do not display  the temperature in Shabbat mode. Moreover, some models completely disconnect the thermal regulation. If your ice cream melts when the fridge is full, or if your salads freeze when it's empty, the timer can save you!