The flexible heat mat is 17 watts and can be wrapped around or placed on top of your Kombucha Keg. A perfect accessory for continuous fermentation. This will ensure a constant temperature suitable for efficient fermentation of your Kombucha tea. Perfect for the Canadian climates.We recommend you do a test run first. Use the same size vessel as you would for your ferment but fill it with water, allow it to sit 12-24 hours and then test the temperature. Another method to decrease the temperature is to add a few coins between the container and the heating pad/mat. Do not use towels or block off the airflow as this may create a potential fire hazard.- Size: 10 x 20.75 inches