Review on ANBANGLIN Auto Shut Off Coffee Warmer For Desk: Mug Warmer For Coffee, Tea, And Wax Cups, Heating Plate For Hot Beverages (Black - Mug Not Included) by Amber Anderson

I use this every single day and it is worth every penny. The glowing "power" button shows red for hottest setting, purple for med-high, blue for low, and then press one more time to a blinking red which tells you it's cooling down to power off. I find it keeps most mugs hot and the smaller the cup, the more chance it will actually reheat coffee that cooled down. The big mug in my picture stayed hot for an hour with the setting on high. I would buy again in a heartbeat.