Nipple features 2 holes ideal for babies at least 1 month old and breastfed babies of all ages Clinically proven to reduce colic Philips Avent Classic+ and Anti-colic bottles and nipples are compatible. Anti-colic bottles can be used with Classic+ nipples and Classic+ bottles can be used with Anti-colic bottle nipples. BPA free Dishwasher safe Philips Avent SCF422/27 Anti-colic baby bottle Slow Flow Nipple lets infants control the flow of milk like with breastfeeding, which can reduce spit-up and overeating. Philips Avent's anti-colic valve flexes to keep air in the bottle and out of your baby's tummy, a feature that reduces fussing and colic. In a clinical trial, two-week-old infants fed with a Philips Avent Anti-colic baby bottle bottle experienced less colic than babies fed with a conventional bottle, with the greatest difference seen at night. Appropriate for babies at least 1 month old, these dual-hole nipples offer a slow flow. The nipple is made of flavorless, odorless silicone that resists discoloring and stickiness. The nipple's soft, rounded shape promotes feeding for babies who nurse from both the breast and a bottle. The Anti-colic baby bottle BPA Free nipples are dishwasher safe and can be sterilized by boiling for five minutes or by using a Philips Avent steam sterilizer. We recommend to use the Anti-colic baby bottle nipples with the Anti-colic baby bottle or Classic+ bottles. Philips Avent Classic+ and Anti-colic bottles and nipples are interchangeable. Anti-colic bottles can be used with Classic+ nipples and Classic+ bottles can be used with Anti-colic nipples.