USB Heat Vest
You can buy a USB Heat vest from Wish with built-in heating panels to keep you toasty while you are out in the winter. The vest comes in an array of sizes and features three heating zones.
It works with a USB cord and the power button is clearly visible on the chest. It heats the back, neck, and stomach.
The catch is that unless you want to plug into your computer or a charger at the desk, you need to buy a mobile power back to use this when you are outside.