Which thermal food jar is good to keep food warm for e longest period of time? Those food jars with 2 compartments/storage. Any recommendations? About 500ml-800ml.

I used Thermos for my elder boy.. usualy I only put porridge to bring out for dinner & put in immediately after u off d stove. sometime if can't finish & I forgot to wash when we got home at nite, d next morning I open the porridge still warm. Bought this from Isetan Nex.