Reusable SS material is used more and more in future.This item 530ml Stainless Steel Reusable Tumbler With Straw is made of 18/10 stainless steel.Can pass FDA certificate. Stainless straw is also one light design of this item. Now plastic-free policy are done by many countries, so our design with reusable SS for the straw too. The lid can proof to leak out. This tumbler has the good appearance and multi-function using. Such on outdoor, camping, coffee mug, cooler,and travel too. “What you like, what we do!”