Several tiny openings modelled on a mother’s breast give an optimal, smooth and natural flowWide, flexible lip rest with extra-soft teat tip similar to a mother’s nipple encourages acceptance. Innovative anti-colic vent helps prevent air being swallowed. Specifications - Silicone- Pack dims: 6.4cm x 10cm x 6.8cm, 0.05kg- BPA-free- Fits all NUK Nature Sense Baby Bottles- Suitable from birth, Size Medium for medium flow (6 tiny openings)Cleaning Bottles, Teats & AccessoriesBefore first use place in boiling water for 5 minutes, use sufficient water to avoid damage. To ensure hygiene, clean thoroughly using mild washing up liquid and sterilise before every further use. We recommend using the NUK Steriliser for sterilisation. Always dismantle the bottle for boiling or steam sterilising (temperature above 80 °C) into its component parts and leave it open, otherwise deformation may result. Certain foods (e.g. carrot juice) may discolour the material or affect it's odour. This has no effect on the fitness for use or safety of the bottle. Teats and bottles should not be cleaned in a dishwasher - dishwasher detergents can cause material damage! For sterilisation in a microwave oven we recommend using the NUK Microwave Steriliser (please follow instructions).Store hygienically in a dark place.For Glass Bottles Glass Bottles may break. Do not use metal spoons to stir the bottle - this could cause hairline cracks which could result in fracture when hot feed is poured in. Never use force to seal/unseal. Replace the bottle if there is the slightest sign of damage e.g. cracking.For products which include a seal or protective cap: keep all component parts not in use out of reach of children.For Latex Teats Produced from natural rubber latex which may cause allergic reactions.Warnings!Always use this product with adult supervision. Never use feeding teats as a soother. Continuous and prolonged sucking of fluids will cause tooth decay. This applies in particular to sweetened drinks and fruit/vegetable juices. Always check food temperatures before feeding. Always check the teat for signs of excessive wear by pulling the teat in all directions before each use especially when the child has teeth. Replace when sticky from use, visibly damaged or showing signs of tears or bites to avoid danger of small parts being swallowed. For safety and hygiene purposes replace teat after 1-2 months use.Do not expose the teat to direct sunlight/heat or leave in disinfectants (sterilising solution) for longer than the stated time as this can damage the teat. Store hygienically in a dark and dry place. Do not dip in medicine! If the bottle is damaged from the inside (e.g. by scratches) it should be replaced for hygiene reasons. About NUKTo make life easier, you have to understand it first. Since 1956 NUK has been listening to the trusted experts: midwives, doctors, nutritionists and especially mums and dads in order to learn about the needs of both parent and child in those precious early years.Regardless of whether you are combining bottle and breastfeeding or would just like to get your baby used to drinking from a bottle – the NUK Nature Sense Teat offers you and your little one a natural drinking experience: the several tiny openings of the teat were modelled on the milk ducts in a mother’s breast and make the NUK Nature Sense a bottle with which babies can enjoy a familiar feeling when drinking and, above all else, a natural flow. The soft zone is gentle on the top of baby’s delicate mouth and the wide lip rest lets your baby latch on in a natural way. The innovative anti-colic vent makes it possible to drink as if from the breast without a pause which helps prevent your baby swallowing air and reduces the risk of colic.