Pigeon’s original nipple design. Research conducted on baby’s oral devlopment shows that baby suckles breastmilk by moving their tongue in a smooth, wave-like motion. This is called ‘Peristaltic motion’ and is the natural way a baby feeds. Pigeon teats have been designed to mimic and promote this natural sucking action. Pigeon teats will reduce nipple confusion between breast and bottle. Suitable for slim necked bottles. L size for babies 9 months+ with a round hole at the teat tip. Super-Stretchable Teat section has an "accordion-like" portion that enables it to stretch in response to the peristaltic movement of the baby's tongue. Ultra-Soft Silicone The nipple's surface is very soft, yet it does not collapse easily. Made from thick ultra-soft silicone material, the nipple has similar elasticity to that of a mother's actual breast. The dome-like shape makes baby's mouth open naturally, supports its mouth softly and fits its lips gently.