THE KOMBUCHA MAMMA YEAR ROUND HEATER - with DIMMER CONTROL - Rotate the the dimmer left to right to achieve the desired heating range. It is a common homebrewers refrain: "How can I keep my Kombucha brew warm, especially in Spring, Fall and Winter?" Until now, standard beer heating belts and weakly powered seedling mats were the only choices available. If youre house is cold, they wont help! The Kombucha Mamma Year Round Heating System w/Dimmer was designed by Kombucha Kamp with the help of a thermodynamics engineer. Designed for WARM TO MODERATE CLIMATES, the state of the art ultra-thin construction & patented heating technology makes for more uniform heat distribution. Wrap around one vessel or lay behind several vessels to keep them all warm. This is a powerful little mat but is also very safe to use. We recommend using it on the sides of the vessel rather than underneath so that the yeast isnt over stimulated. ***FEATURES: Warms the brewer area by about 5-20°F over ambient temperature to maintain the ideal temperature for Kombucha fermentation; No heat wires or thick pad; Almost the entire surface of the mat is covered by the heat strips creating an even heat distribution; Moisture sealed electrical connections (Do not submerse in water); Ultra-thin Super durable construction; Heat Strip & power cord are UL Listed Components; 110-120V AC Power ; Uses 18 watts of power; Approximate Dimensions: 4" Width x 24" Length; Assembled in USA and all components made in the USA (except power cord) which means your friends and neighbors have a job!; Comes with 1 Year Hassle Free Guarantee!; FREE Thermometer Strip included; Works with any ferment! This package ships via First Class USPS.