The nuk nature sense 150ml learner cup is designed for a soft transition from breastfeeding to independent drinking. featuring an extra-soft and wide lip rest, an innovative anti-colic vent and soft feel handles for easy grip, the nature sense learner cup means learning to drink independently from a cup is made easier for your child. the bottle features a 6 – 18 month silicone non spill spout which reduces mess, making it ideal for active babies.for safety and hygiene purposes we recommend that you replace spouts after 1-2 months of use or whenever they start to show signs of wear. prior to sterilisation we recommend using the nuk baby bottle cleanser, it’s natural formula removes dried on milk protein, pulp and juice residues more effectively than hot soapy water alone. to sterilise cups and spouts we recommend using steam, cold water sterilisation or a nuk steam or microwave steriliser. we do not recommend dishwasher sterilisation as this can cause material damage.bpa (bisphenol a) free.