ENVIRONMENTAL-FRIENDLY MATERIAL: We use Tritan Plastic as this wine glass material, this is a environmental-friendly material which doesn't contain any toxic chemical composition, Tritan Plastic is the specify materials for infant and child products in Europe and the United States, free of BPA and BPS, unbreakable and reusable, It’s no pollution to the environmental and you no longer worry about they will broken easily like crystal wine glass! UNIQUE FUNCTION-DISHWASHER SAFE: This stemless wine glass have the unique function but other ordinary wine glasses didn't have, wine glasses are dishwasher safe on top rack, the thickness and heat-resistance of the wine glass allows you to heat up it, they can withstand repeated washing in dishwashers up to 200 F, but please note put them vertically in dishwasher and do not squeeze reciprocally, at last wiping gently with a soft fabric after washing to keep them look better! DURABLE AND STURDY TO STEMLESS BASE: No any risk of breakage because of the durable and shatterproof Tritan Plastic material, the stemless wine glasses get rid of the long stems design, not anxious of the stem would be bending anymore, not worry about the base is not stable anymore, they are nice enough to have with guests over, the stemless feature make them more durable for daily use.