Ice trap retains ice or beer foam made of break-resistant polycarbonate for ultimate durability Polycarbonate (PC) is resistant to staining, breaking and chipping 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.