24 hours cold TempShield double-wall vacuum insulation Leakproof when closed Pure taste with no flavor transfer Wide Mouth opening is ice-cube friendly Bottle fits most backcountry water filters BPA-Free Dishwasher safe Flex Straw Cap not intended for use with hot liquids Not for use on a stove, in a microwave, or freezer Bottle fits all Wide Mouth caps and lids A 40 oz Wide Mouth water bottle with our leakproof Flex Straw Cap*easy to fill, easy to drink. Open it up, add your ice, and flip to sip. The insulated stainless steel keeps it cold for up to 24 hours.