Hi all l bought what was called at the time a Trans mit must be nearly 25 years ago made by a mob called MM developments lovely piece of kit kept my pandies warm and dry and still acomodates the newer type of transmitter with screens and a christmas tree of switches and twiddly knobs.

If the battery was along side the motor you could wrap some fleece fabric over both and use the heat from the motor(s) to keep the battery warm.👍😊

Actually I am more concerned about how to keep the Transmitter dry in misty wet weather than warming my hands. Sometimes here in Canada we can be sailing our boats when a sudden squall will pop up. How to keep my transmitter dry under those conditions is my main concern.

In Canada we have hand warmers to put in our gloves that work very well.

Shrug off the coldest days with these "pocket furnaces."
Slip warmers into gloves, pockets, hard hats or between layers of clothing.
Shake to use, air-activated. Heats up to 55°C (130°F).
Safe, odorless and disposable.
Heats up to 10 hours.

If it's really cold you can add the "tyre warmers" available from Hobbyking

Same here. I made a nice warm cosy out of a yard of leatherette - see below:

Many years ago I used to do a lot of glider slope soaring. Standing on top of a hill on a windy day in the winter soon numbs the hands. I solved the problem by using an old tea cosy with a hole in the top. if the was rain around then a plastic bag was used over the top of the cosy.
Alan

HI Ron, I have a similar one, very useful in the colder months, stops the wind on your hands. As a by product it keeps the transmitter batteries warmer, so they last longer, got to workout how to keep my motor battery warm to get longer sailing times!!!