Review on ☕ COSORI Mug Warmer & Coffee Cup Warmer: The Perfect Desk Coffee Gift for Home and Office Use by Julie Serrano

No matter which cup I use in this warmer, the temperature is different everywhere. Doesn't keep drinks hot. The temperature sinks. Later it increases by a few degrees and then decreases again. I've used shallow cups, small cups, half full cups. That sucks. I tried calling the company but no answer because COVID wanted me to email. I pulled out the product data sheet and suspect it is a defective heater. I'd rather have the company call me than exchange emails. The time for a return has expired. I give up. So I bought a Yeti thermal mug that keeps my coffee hot for a while. This heater doesn't cost $30.