And it is difficult to beat a hot water bottle as a low-tech solution as
long as the galley stove is available. Even works with sea water!

Chuck


8906 wrote:
I find that well made sleeping bags get plenty warm from body heat.
But I use heating pads or small heating blankets to warm them up
before entry cuz I'm a woos on real cold nights and that first
5 minutes inside is much nicer when it's already warm.