MobileSharpElegant Clear Double wall Glass Coffee Cup Tea Milk Glass Mug Cup 100% brand new and high quality with competitive price Purely manual blow-molded heat resistant cup and there may be some difference between the cups. The instant bearing of temperature range: -30~150. Suggest to clean the cup with neutrality detergent when used before the first time. Do not soak it in the water to avoid water or moisture getting in to the double space.