USB 3-Level Adjustable Temperature Heating Pads, 5 PCS | Quickly warms back waist neck, composite fiber, wearable warmer for outdoor office home, Black

These little heating pads are so well made! The thermostat is a precision controller. I have used them in clothing and (computer) luggage with 100% success. We work in field labs in all kinds of weather, so it is especially important to keep the computers and bio-genes at the right temperature in vehicles that are not running. Now we are putting them inside our electric lunchbox stoves inside the insulation, under the food tray to keep things at 98, 113, or 144 F without having to plug into the 12V or 110 circuits where there is no thermostat controller. That has a profound positive affect on life, budget, and our schedules on the road. Further, we now use them to keep our CO2 cartridges at 110 F in our sling-packs for peak performance in freezing temps and +60% more power when its 72 F outside. I figure these little heaters are the cause of about 2-extra-hours per person, per day. Pretty cool for a hot little item!

Horrible. Don’t waste your money. I put them in my socks and gloves, and after an hour, I barely feel anything. As I write this review, I have wires dangling all over me. I have bad circulation in my hands and feet and thought this would help take the edge off. It doesn’t. Takes forever to heat up and even at the highest setting provides next to nothing

turns off after maybe an hour or so. Tried different power supplies, environments. Note: pulls 2 amps an high temp. At the lower temperature settings, it still pulls 2 amps, but only for a few seconds at a time.

You'd get more heat rubbing your hands together as compared to theses, maybe 100°F on the "hottest" of the 5 pads. Received them today, sending them back tomorrow. No instructions packing was pretty pathetic, product was no better.

No battery pack!

My Yorkie had 4 puppies and this worked great for keeping their body temp up when mom wasn't there with them. Very pleased!