What kind of insulated lunch box can keep warm for more than 6 hours in the coldest winter, and the food is still a little hot? Please talk to someone with experience.

basically, in your case, it is not very likely to keep the temperature for more than 6 hours.

A better incubator can hardly last more than 6 hours under your condition.

However, there is the stupidest way, that is, to buy a large thermos. There is a small thermos in it.

of course, what you eat is in a small thermos, and then in a large thermos! Wrap it in a cotton bag.

this is my previous method, which takes a long time to keep warm, but in the end, cooking will become a stew. It's best to cook fried rice every day. Then get some meat or something, cooked vegetables!

of course, if the economic conditions are enough, you can buy some better thermos bottles! ! !