Plastic quality, and operating in defiance of common sense ...

Operation: a timer button allows the oven to start, and a button to adjust the temperature.
To stop the oven, think to put the temperature to 0, otherwise the oven continues to heat pdt time which you have set the timer. It is not very smart and above all, we tend to want to turn off the oven by turning the timer knob backwards which could irreparably labîmer seen that this is a bad plastic.
I do not recommend this model because I already know that with two teen at home, this button will not last long. (I bet sold at retail cost an arm button ...)