Bitz mugs m. Hank made of gray stoneware. Mat gray on the outside, glossy light blue inside. Contains 30 cl. DIA. 8.5 cm. H: 10.0 cm. The stoneware is made with a beautiful reactive glaze that gives it extra glow. The stoneware can withstand machine washing, microwave and oven up to 220gr. Bitz Matte and Reactive Glaze makes each product unique. Scratches and cutting marks will be visible. This is not an error. Bitz concept.