Coffee Mug Warmer, ONEVER PU Coffee Warmer Plate with Automatic Shut Off Temperature Up to 185℉/85℃for Desk & Office Coffee Accessories (Blue)

Once I warm a container of food, I can place it in a cooler with this and a USB battery pack, and it'll stay warm.

It looks like the advert and is pretty and arrived safely on time, but it doesn't do the job. It's now just a pretty coaster with a USB cord on it. It barely warmed when plugged directly into a laptop; plugged into a dongle, it's even less warm. It's a case of you get what you pay for; this doesn't do the job, period.

I really wanted a warmer that was usb plug-in capable. I liked that it didn't get so hot as to burn me but it took a long time to warm up and only slowed the cooling process down by some. It was better than not having it but left a lot to be desired... and then it died. I don't think I've even been using it for a month, but if so, not much more than a month.

It doesn’t get hot enough to keep my coffee even Luke warm.

Did not even keep my coffee lukewarm. Super disappointed. Made the mistake of buying one for me and one for a co-worker. I was embarrassed that I gifted this and it failed miserably.

Only use two week, 5 time, now dead.

Worked for a few weeks but now nothing, no heat, broken

This keeps my mug and its contents warm, not hot. It doesn't warm up room temperature beverages. It also doesn't automatically shut off.