The IceFlow Flip Straw water bottle by Stanley is made of 18/8 stainless steel with lightweight AeroLight technology. Double-wall vacuum insulation keeps water ice cold for hours, while the spun steel construction makes the bottle 33 % lighter than standard stainless steel bottles. The Flip Straw 2.0 lid has a large drinking opening and a built-in straw. The folding handle makes the bottle easy to carry. A practical water bottle to take to yoga or on the go.