Take your lightweight, stainless steel water bottle wherever you go! Our insulated water bottles can contain 350ml and are made of the best quality steel — 18/8 stainless steel. This type of steel has a thermal function which will help you to keep liquids warm up to 12 hours and cold up to 24 hours. Sip & Go leak proof lid is made of PP and is BPA free. The lid comes with a food grade silicone straw and you will get 1 lid cleaning brush to keep your bottle clean.