12 oz. Food grade stainless steel. Double wall, vacuum insulated. Hot or Cold Beverages. Allow liquids to cool to a drinkable temperature. Wash before use, handwash recommended, do not soak or submerge. Do not clean with bleach cleaners containing chlorine. Not suitable for microwave, cooking or freezing.
 
I have used a Mary Square coffee cup for a year now, and have not noticed any degradation of the floral patterns on the cup.