It is easy to use, the tea light candle in the center of the glass heater, and then put the stainless steel it. Put the already brewed tea on a heater to heat and keep it warm for several hours. Glass tea warmers are perfect for all teapots and most other teapot brands. This handmade teapot heater is borosilicate glass and can keep tea warm for 2-3 hours with tea light . The teapot heater is handmade borosilicate glass and stainless steel. Comes with a tea light candle; a tea light candle can heat for several hours in a soft, flickering candlelight. The teapot heater is available in two sizes and fits most teapots; the soft and round shape helps to highlight the teapot placed on top.