Bottle Material: Food cap - polypropylene Nipple -silicone Bottle - polyphenylsulfone (PPSU) Features: Top grade materials: Bottle is made from Polyphenylsulfone (PPSU) material with higher heat-resistance degree and excellent durability. Nipple is 100% silicone, super soft and flexible to allow for natural and smooth tongue movement. User friendly design: Nipple's wide base helps Baby to open their mouth widely, encouraging steady peristaltic motion. It is also to prevent Baby's lips from reaching the cap during attachment. Baby will then able to form a solid seal on the silicone for more effective sucking. Wide-neck Streamline Bottle: The streamlined shape makes it easy for mothers to hold and keep clean. Air Ventilation System (AVS): For stress-free drinking with minimum air intake during feeding. Pigeon bottles can be boiled, steamed, microwaved to sterilize or through the ultraviolet ray to sterilize. BPA Free Color: Yellow, Green