All epoxy based tumblers are made with a professional grade FDA compliant resin. Drying with a glass like finish, this epoxy resin has UV inhibitors to prevent yellowing and provide long term clarity, as well as, being heat rated to 500 degrees.
**It is recommended to hand wash tumblers only. Not dishwasher safe, not microwave safe. Avoid extreme heat exposure Handmade with love, please handle with care.