The GoSili Reusable Silicone Straw Cup comes with a universal silicone straw lid that stretches over the rim of the cup creating an airtight fit (making it virtually spill proof!). The universal straw lid can also be used with almost any cup or glass, making it a straw cup in a matter of seconds – bonus! GoSili reusable cups are 100% European grade platinum silicone and feature an embedded stainless-steel ring that prevents the cup from collapsing when gripped. Perfect for small hands, and big squeezes! GoSili cups are incredibly durable, can grow with your child, and are meant to last a lifetime…which is kind of the point! It’s an easy, sustainable solution to kicking the single-use cup habit whether at home or on-the go. All components of the GoSili cup are dishwasher and microwave safe and can be boiled to sterilize. On behalf of our planet, thank you for making the choice to waste less, and GoSili.