The Philips Avent Ultra Air pacifier for babies 18+ months is designed with a lightweight, breathable shield for sensitive skin. Four (4) extra large holes in the shield allow for maximum air flow, so skin stays drier while soothing; 84% of moms agree!* Plus, the nipple is specifically designed for growing toddlers because it's made of tougher silicone than other pacifiers. The pacifiers are BPA-free and dishwasher safe. Each pack of 2 comes with a sterilizer / carrying case that can be used to sterilize the pacifiers with water in the microwave. *MetrixLab Home Placement Test with 118 U.S. moms, 2017