DURABLE, LEAKPROOF FLASKS: Made from unbreakable 18/10 stainless steel, Pioneer Vacuum Flasks are perfect for hikers, climbers and others who love the great outdoors! VACUUM INSULATED: These flasks keep your drinks warm for up to eight hours thanks to the innovative double wall insulation. IN-BUILT CUPS: The ideal picnic flask, you can enjoy your favourite hot beverages anywhere and at any time! SHOP THE FULL RANGE: Three colours and two sizes available.