Suppose the baby will wake up at 4:00-4:30am and mom goes to bed at 11:00am. Mom can take the breastmilk out of the refrigerator and put it into this breastmilk warmer, set it to the appointment mode and set the time for 4 hours, then during the 4 hours from 11-3pm, the warmer will enter the low temperature preservation mode to ensure that the breastmilk won't be spoiled. After 3 o'clock (reservation time), the milk warmer automatically jumps to heating mode, heats up the bottle in the warmer to the set temperature, and continues to maintain a constant temperature for 2 hours, so your baby can drink hot milk when he wakes up at any time during the period from 3:30 to 5:30 pm. The ZeraPolars Bottle Warmer is designed for this purpose!