Ferroday Stainless Steel Thermometer Dial Thermometer 1/2 NPT Homebrew Kettle Thermometer With Lock Nut & O-ring ( 0-220&ordm;F, -10-100&ordm;C) Dual Scale Dial Thermometer : 0 to 220  -10 to 100. Our Dial thermometer monitor show both fahrenheit and celsius Food Grade Material: The dial thermometer is made of 304 stainless steel. The red washer is made of food grade silicone. So our dial thermometer have good heat resistant & corrosion resistance that can last a lifetime Automatically & Accurately Measure : The temperature sensor is on the 2 inch probe that features high sensitivity. Only the probe touch the liquid or air and so on, our dial thermometer will automatically test temperature Easy To Read: Our dial thermometer has a large 3 inch glass dial and clear numbers ,so it is easy to read Unique 1/2 NPT Thread Design: 1/2 NPT male thread dial thermometer can be installed on 1/2 female thread fitting. This bi-metal thermometer perfect for home brew kettles &stock pots&mash tuns& fermenter and so on