Tuxton Home Concentrix Round Cup (Set of 4), 8 oz, Black; Heavy Duty; Chip Resistant; Lead and Cadmium Free; Freezer to Oven Safe up to 500F Restaurant grade vitrified china - thermal shock tested, low permeability Tuxton Home products have been used and tested in restaurants Microwave, dishwasher, freezer, oven safe Passes ca prop 65 and all U.S FDA requirements for lead and cadmium exposure. Microwave, dishwasher, freezer, oven safe. Designed for heavy/ double duty use; Can go from freezer to oven to table