With the DOMO DO9142EK egg cooker, your eggs will be perfectly cooked in no time. Boil 1 to 7 eggs, however many you want to eat. You choose how hard you want them to be with the turn of a knob: from soft to hard-boiled and everything in between. Fill the water reservoir with the supplied measuring cup. An egg piercer has been built into the bottom of the measuring cup. Tip: Pierce a hole before you boil the eggs and they will not crack.