Upgraded version: 19cmX 18cmX 9cm, operating temperature: 60C - 350C, made of high strength aluminum alloy.Four blades provide bigger and wider hot air, circulates about 210CFM.No Batteries or Electricity Required: The stove fan uses heat from the stove surface to rotate, adjusts its speed automatically with the temperature of the stove surface, and no batteries or electricity required, and only needs heat from the hearth torotate the fan, which is in line with the current concept of energy saving.Quiet: The noise is less than 25db, you don't even know the fan is there, but you will still feel the heat.The only moving part is the blade assembly.Say goodbye to terrible noise You will enjoy warm air in a quiet and comfortable environment.Easy Operation: No assembly needed, just put it on the stove top, the fan will rotate with the temperature getting higher and higher and the fan speed will change automatically, increase the heating efficiency of your stove or fireplace