Pigeon Flexible Slim Neck Nipple Size L x3Backed by over 60 years of research on babys natural suckling motion, our Flexible Slim Neck Nipple is so soft it flexes to the movements of babies mouth and bends naturally to babys mouth movement. The nursing bottles Air Ventilation System (AVS) reduces intake of gas, a potential cause of colic. For 9+ months. L cut enables faster flow of milk. Upgrade to this size if baby is not satisfied with Y cut. 2 pcs per pack Super Stretchable Teat section