Rapidly cooling / warming to 55 Degrees - No battery, no electricity needed - Just shake to change the temperature to 55 degrees, mid warm Especially useful flask for those who have a baby, elderly etc Material: Food grade PP & stainless steel Litre: 280ml Size: 76.2 × 221mm Change the water temperature to 55 degrees: • Firstly, fill the flask with hot boiling 100 degrees water, shake for 1 minute, water temperature will become 55 degrees mid warm water! • Then, pour the cold/room temperature water into the flask, shake for 1 minute, the cold/ room temperature water will turn 55 degrees! (But if pour hot water again for this step, result will be affected. Need at least half to an hour interval, then can pour hot water & become 55 degrees)