"100% Plastic-free infant bottle easily transitions to sippy bottle, straw bottle, sport bottle, or snack container with medical-grade silicone components from Pura. Baby Grows...Bottle Evolves. Includes soft silicone travel cover, bright-colored sleeve, and slow flow nipple with anti-colic vent tube Dishwasher Safe, food grade #304 (18/8) stainless steel and medical grade silicone contains no BPA, BPS, EA, PVC, phthalates, or other toxins and no internal lining to ensure nothing ever leaches into your beverage Internal volume marks for easy measuring Compatible with other Pura silicone components and accessories; General Instructions: Wash before first use. Boil for 5 minutes to sterilize. Remove the sleeve from the bottle at least one time per week to clean between the bottle and sleeve, more often in humid climates. Dishwasher safe. How to install sleeve: Add baking soda to the inside of a dry sleeve then slide onto the bottle. Rinse thoroughly. OR At the sink, spread a pea-sized drop of liquid dish soap inside the sleeve then slide the sleeve onto the bottle. Rinse thoroughly."