The OXO LiquiSeal Travel Mug is the perfect durable, spill proof everyday mug. Three silicone seals prevent spillage, while double walls insulate your drink keeping cold drinks cool and hot drinks warm. A shatter resistant exterior makes this thermos durable. With a drinking spout that is easy to open and close with one hand and also curved for comfort, it's really convenient. Made of plastic. Hand wash only - not recommended for the microwave.