The Lifeventure Vacuum Flasks come supplied with both a one-touch & a screw in stopper & will keep drinks hot for up to 8 hours, or cool for 24 hours. The Lifeventure Vacuum Flasks are high performance vacuum insulated, with a stainless steel lid that can be used as a cup & a sleek design for simple storage. There are 2 sizes of flask in our range - 0.5 Litre & 0.7 Litre. Each one comes with two stoppers; a one touch stopper & a simple screw top stopper. Both tested in the Lifeventure laboratories these are highly efficient insulating vacuum flasks. The vacuum is created from a heating & cooling manufacturing process that is more reliable than many other flask designs.