Cold hands/feet are a consequence of your body deciding that it needs to reduce blood flow (which implies heat loss) to those extremities, in order to keep your

Cold hands/feet are a consequence of your body deciding that it needs to reduce blood flow (which implies heat loss) to those extremities, in order to keep your core temperature stable with minimal energy expenditure. Therefore, heating your torso might work better than trying to heat your hands. Googling for electrically heated garments typically leads to some dodgy looking cheap products though. I would have a look at body warmers sold by power tool brands to go with their battery platform. E.g. I already have LXT batteries for my Makita power tools, so I'm considering buying something like the DCV202Z vest.