PLS Set of 12 x Premium 500ml Tumbler Drinkware. Made from High Quality Polycarbonate, Stylish &Crystal Clear and Vitually Unbreakable. Freezer & Dishwasher Safe. Our NEW SERENO range of Quality Polycarbonate Drinkware allow cold drinks to be served and remain at a cool serving temperature for longer than drinks served in conventional glass or ceramics.