This wine cup is made of PCTG material, so that its transparency and dencity are very similar to glass. It’s hard to be stained even for a long time use. but it’s easy to wash and clean and can bear large pressure. Great wine cups for home, hotel, restaurant and other places. – Dishwasher safe. Shatterproof with high temperature resistance for safe and durable use. – Totally transparent which is super familar to glass cups. More elegant and high-end apperance.