This particular tumbler goes from white inside to blue in the sun.
All tumblers are made with FDA complaint epoxy using stainless steel and double walled tumblers.
Can be done on 14oz, 20oz and 30oz.
This item is handmade there may be some imperfections. These imperfections will not affect the functionality of the tumbler. Since they are handmade no two tumblers will ever look exactly the same.