The master vacuum bottle is made for the toughest of the tough for those who demand the very best in durability and performance the quadvac insulation keeps hot drinks hot for 40 hours no matter what you are doing or where you are going this bottle is ready when you are quadvac insulation keeps drinks hot 40 hours cold 35 hours or iced 160 hours 10mm 188 stainless steel ndash the strongest yoursquoll find by far rust proof naturally bpa free steel lined pour through stopper ndash no plasti