Ovente CH112 12V Portable Travel Car Immersion Heater, Black Always remove the plug of the immersion heater before and after use to avoid breakage Travel Size Immersion Heater for Hot Water 12Volts of power, 150Watts fits into car's 12V lighter soccer Best results if used with water; Use with glass, ceramic or stainless steel containers only; Portable and convenient to use Metal-clip attaches easily to your mug