This plastic glass is durable and tough tulip-shaped tumbler glass is manufactured using space age, virtually unbreakable, polycarbonate plastic. Being virtually unbreakable, these tumbler glasses are ideal for kids and the elderly, camping, boats, caravans, indoor and outdoor events, and around wet areas such as swimming pools. These tough polycarbonate plastic tumbler glasses are fully dishwasher and microwave proof and can withstand temperatures from -40C to +120C. Combine the glasses durability with being reusable, stackable, recyclable and environmentally friendly, and this product really is a winner. No more broken glasses these glasses are yours for keeps!