The Igloo Stainless Steel Travel Mug is crafted from double-wall vacuum insulated stainless steel with internal copper lining for superior temperature retention. Drinks will stay cold up to 48 hours and hot for 6. The Flip ‘n’ Slip lid is fully leakproof when closed and the two-part straw includes a silicone straw base and rubber sipping top built with a stopper to prevent spills. The flat surface “thumb-grabber” along the side aligns with the mouth opening on the lid for quick sips.The sweatproof powdercoating and ergonomic handle makes it easy to grab and go. Travel worry-free with the non-slip rubber bottom and cupholder friendly base.