Kozii uses a low temperature, nutrient-safe water bath that is safe for ALL bottle and bag types. The water in the warmer is about as warm as warm tap water. This allows caregivers to warm breast milk without exposing bags and bottles to dangerous steam, hot or boiling water, or the microwave. Kozii uses patent-pending technology, specifically designed to eliminate the risk of hot spots, nutrient damage, and dangerous chemicals that can be released from plastic bottles at high temperatures. Kozii can safely accommodate breast milk, formula, storage bags (frozen or thawed), liner bottles, plastic, glass, food jars, etc.