Because you can never have too much C8H10N4O2.Caffeine molecules support the dynamic polygonal structure of this extremely geeky coffee mug. Each atom is visible and is identifiable by its size, with the single and double covalent bonds represented by single or double lines.This is real, non-toxic glazed porcelain, fired in a kiln. The size of a regular coffee mug, holds 7 ounces (207 ml).Looking for a smaller, espresso size? Available here! Prefer chocolate instead of coffee? Check this one out!