Kitchen Gadget Hot Magic Color Changing Egg Rite Egg Timer Time Cook Boil Eggs Thermometer, Set of 2 Egg timer; Hand wash & Can be cooled on the counter Placed in pan with eggs, timer darkens as eggs cook -- Not to set a timer or guess when the eggs are Calculates cooking stages precisely by temperature, not loosely by time -- Reacts to heat just as an egg does & eggs come out just right. Great for soft boiled eggs and the timing was right as the color changed for those who have problems with timing eggs. Easy to see color change when submerged as the pic shown -- As the timer heats up the Red face changes color, indicating soft, medium, hard and stages in between