CafePress - Math Genius Mug - Unique Coffee Mug, Coffee Cup Small White & White / Black Coffee Mug is 3.75"x3", 11 oz capacity. Mega Mug Option is 4.75"x3.25", 20 oz capacity. Durable white ceramic with easy grip handle give a classic coffee mug look and feel. Coffee cup designs are professionally printed. Make someone smile with funny, cute, vintage, or expressive artwork! Microwave safe. Dishwasher safe, top shelf recommended. IMPORTED. We offer 100% money back guarantee, so you can buy with confidence. Your satisfaction is our promise, and returns/exchanges are made easy.