This product is a slim neck teat, with double thickness silicone to ensure ideal softness and flexibility for latching on comfortably and easily. Each teat also features a unique venting system to minimize swallowed air and help reduce colic. This teat opens only when the baby sucks. The harder the baby sucks, the more the teat will open and vice versa. Pigeon's original nipple design. Research conducted on baby's oral development shows that baby suckles breast milk by moving their tongue in a smooth, wave-like motion. This motion is called 'Peristaltic motion' and is the natural sucking behavior of a baby. Pigeon teats have been specially designed to mimic and promote this natural sucking action. Pigeon teats have been designed to reduce nipple confusion between breast and bottle.