The Yeti Rambler cup is ideal for hot and cold drinks. It's dishwasher safe and easy to clean. The cup is durable and well constructed. The Rambler cup is double-walled vacuum insulated stainless steel. The optional magnetic slider lid keeps your liquid from spilling and also helps insulate. The Yeti Rambler cup is so popular because it's equally functional in the home and on adventures. , People adore their YETI products and the popularity is justified. YETI products keep your cold drinks colder for longer and hot drinks warmer. The double wall insulation makes the gear sweat-free.