My extremities have been suffering with the cold. Solved the hand problem with the S-Boston handwarmers, also warm the core if pocketed right
Moving onto feet I got a few of these (foot warmer item number 220702393539). I used them first tonight in a lot of snow and bitter cold out. They did put out some heat in fairness, but will need to give them another go.
On the other hand, am quite happy with the liner socks and heat holder socks I got Looking to get new insoles, then install the foil heat reflectors in them.