Marquis 2 Piece Set of 21 and 25 Spinner Color:Black Thermos vacuum insulation technologyvirtually eliminates Thermos vacuum insulation technologyvirtually eliminates temperature change within the beverage container bycreating an airless space between two stainless steel walls alleviating body strain and makes this bag easy to maneuver tricky in corners and unexpected crowds with a self aligning magnetic design that ensures your luggage is always rolling right along From a multiple stop handle that promotes comfort rolling for travelers of all heights to tapered expandability that keeps the bag from tipping over when packed full