Made of 304 18/8 stainless steel, these tumblers are highly durable and resistant to breakage and rust. With double walled vacuum insulation, the tumbler can keep your beverages hot for 5 hours and keep cold for 12 hours. Printed in full color, and comes with metal straw and cleaning brush for straw. Slim design fits most vehicle cup holders. Hand wash aka please avoid dishwasher.