does anyone know of a solid product thats usb and or rechargeable , i have seen some of the offers by zippo, maybe a bit too bulk for shoe inserts , and no i don't want disposable hot hand bull crap they last like 3 minutes no thanks .

im looking at some like this but i would have to get some sort of battery system hacked together to make it work , but on the positive side they are cheap , and easy to replace , unlike those 100 plus dollar heated insoles or the unproven heated socks ..????

https://www.amazon.com/Electric-Heat.../dp/B07B2DB8WG

These work for me deer hunting and ice fishing.

https://www.walmart.com/ip/HotHands-...RoCS-wQAvD_BwE

I have had some of those "hot hand" type things that lasted well over 12 hours. If yours are only lasting three minutes you might be doing it wrong or just don't have any sort of winter gear at all and the shorts and a t-shirt with one of those just ain't cutting it.

One problem that can happen with Hot Hands or similar products is that they need a certain amount of air to remain activated. If your shoes are waterproof/windproof and snug fit, there is a chance they are not receiving enough air. I use Hot Hands inside my Bar Mitts for winter riding and they stay warm for 3+ hours.

I have no interest in HOTHANDS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!...................................!!!!!!!!!!!!!!!!!!!!

Use the batteries that are rechargable with the 3.6v stuff. Make sure you carry two sets of the batteries. Usb stuff is going to be 100+ dollars and the ones I've tried dont get hot enough.

Anything electric is going to be impractical due to battery capability. Calculate how many watts are required to keep warm and figure out the size of the battery you need in order to keep them powered for any length of time. I guess if you were willing to cart around a heavy battery you might be able to make it work but otherwise your better off looking at better quality clothing.

I used an electric vest on my motorcycle when I rode years ago. I kept me toasty warm, but needed a lot of power and would only work with a good battery. They must have had a lot of improvements to use heated clothes on a bicycle.

Depends on what you are talking about. Heated soles and gloves work OK. A heated vest would be more challenging, but they do exist.

I run my soles off 18650 cells, one for each foot.
0.8A gives me just shy of 3W for about 4 hours as a theoretical limit.
IRL, I begin to feel the fade after about 2 hours.

Now, "any length of time" may obviously mean different things to different people. But 2 hours full function and one hour more of acceptable function is enough to be useful IMO.

For my part, unless it's really bitterly cold, I don't need to run the heaters continuously. I probably use a duty cycle of 1/3 or thereabouts, which stretches use time considerably.

3 watts is very little heat (my heated motorcycle socks were 13 watts). If the heat is spread over the entire sole, how many square inches is that; maybe 30 for an adult. That amounts to 0.1 watt per square inch. If concentrated in the toe area maybe it's 0.8 W/sq. in. which is pretty puny.

If you figure a similar watt density for gloves the wattage will likely need to at least double and for a vest you'll need an awful lot of watts even just to warm your chest. Starts adding up to a whole bunch of those little 45 gram batteries or a much larger battery.

It's not completely useless but I think you can get a lot more benefit/weight from high quality clothing than you can from heated gear that has wattage that is low enough to run off a battery.

I use Hotronics insoles, they work very very well keeping your feet warm. Not cheap, but this is a case where you get what you pay for. I've used them below zero F and my feet were very comfortable.

OP might want a Rx for the "little blue pill."

but for how long was it very comfortable?

They last about 4 hours on high setting, comfy the whole time.

On Edit - I haven't ridden below zero for 4 hours , but they will last 4 hours and I have ridden several hours with them in the upper teens.

Cool that you are able to get fours hours when its teens. I suspect a couple of hours when below zero?

hahahahaha

I would guess they are going to last a couple hours at least below zero - it likely depends on where you have the batteries. If they are uncovered, yeah a couple hours, maybe a bit more. Covered probably longer. There are 3 or 4 different heat settings, so life depends on where you put those too. Once a person get's moving and warmed up turning them down to a setting lower than 100% would extend battery life obviously.