Cups & Mugs by Contigo. Details:Experience the best in on-the-go convenience with this Byron Vacuum-Insulated Stainless Steel Travel Mug. Designed with a leak-proof lid and a subtly textured grip for secure handling, this 24oz cup offers one-handed drinking without the hassle of misplaced lids or caps. Featuring our innovative THERMALOCK double-wall insulation, your beverages can stay hot up to 9 hours or cold for up to 21. It's the ideal travel companion for your daily commute, outdoor adventures, or casual sips at home.