Can anybody help me out with ratings for a resistor to go inline to reduce the heat of a thumb warmer. There is a resistor inline to reduce the heat on the low side but I want to change things around and add bigger resistor for the low side and make my low side side my high side. Hopefully that makes sense. I don’t know what ohm resistor I should consider. The current resistor is a 5W 12 ohm J, I don’t know what the "J " stands for.
here is a pic
here is a pic
