Oxford Biona Mugs (Set of 6), Pure White Set of 6 Mugs (12 oz each). 100% Lead-Free. Pure white color on top grade Porcelain Made and Designed by Oxford since 1954 High-quality exterior enamel protects against metal marks and other damage. Unmatched thermal resistance from -65F to 500F. Safe for the freezer, microwave and dishwasher