GARMEE Mug Warmer Coffee Warmer - Cup Warmer with 2 Temperature Settings Smart Tea Warmer Portable Beverage Warmer Drink Warmer for Office丨Desk丨Cocoa丨Coffee丨Tea丨Milk丨Hot Drinks（Excluding Cup）In response to the feedback from customers that the insulation effect is not good and occasionally the glass panel will be broken, we have especially upgraded the product. We have used double layer thickened glass in the glass selection, and the heating chip has been replaced by high quality PCT heating plate. We recommend that you use a flat bottomed cup with a lid to achieve the best results. Coffee Cup Warmer 8h Auto Shut Off: Electric Cup Warmer's