The microwave steam sterilizers is a safe, effective and natural way to kill up 99.99% of bacteria from baby bottles, nipple or the other baby accessories in the microwave. There are many ways to sterilize, but the microwave steam sterilizer is quick and easy. They use steam to sterilize, and if you use followed the instruction, they are relatively safe to use. But you never put your baby feeding items directly into the microwave to sterilize. It will not sterilize the bottles or nipples and may damage them. And you have to ensure there are no any mental objects inside the microwave sterilizer.