Clinically-tested: optimal for combining bottle and breastfeeding. Particularly soft teat that is right for the jaw: made of silicone, size 1(0-6 months) M (medium-fine hole = for formula). Helps prevent colic: the improved Anti-Colic Air System. Easy to fill and clean: extra-wide bottle neck. Made of polypropylene. Holds 300 ml. BPA free