Shatterproof polycarbonate. Great for outdoor and poolside beverage service. Sophisticated Styling. Light weight yet durable. Polycarbonate (PC) is resistant to staining, breaking and chipping. Hand washing in bar sinks or 3-compartment sinks will extend life of drinkware. Polycarbonate is sometimes weakened by repeated cycles in a dishwasher and stress cracks are one of the indicators of this. Polycarbonate may be considered dishwasher safe but damage resulting from washing may vary depending on temperature and location in dishwasher.