I am interested in an isothermic bag to carry my lunch. What characteristics should I look for when looking for which one to buy?
If I understand correctly regardless of each one, adding ice packs is critical?

Update:
Usage: carry cooked food (chicken, beef, rice, pasta) etc straight out of my fridge to the way to the office. My understanding is that such bags can't keep it in proper temperature for hours but should be able to keep it in a very good temperature at least till I get to somewhere I can put the lunchbox in a fridge. Also has to be small and easy to carry

I am interested in an isothermic bag to carry my lunch. What characteristics should I look for when looking for which one to buy?
If I understand correctly regardless of each one, adding ice packs is critical?
Also is there a difference between an insulated bag and an isothermic bag?

Update:
Usage: carry cooked food (chicken, beef, rice, pasta) etc straight out of my fridge to the way to the office. My understanding is that such bags can't keep it in proper temperature for hours but should be able to keep it in a very good temperature at least till I get to somewhere I can put the lunchbox in a fridge. Also has to be small and easy to carry

I am interested in an isothermic bag to carry my lunch. What characteristics should I look for when looking for which one to buy?
If I understand correctly regardless of each one, adding ice packs is critical?

I am interested in an isothermic bag to carry my lunch. What characteristics should I look for when looking for which one to buy?
If I understand correctly regardless of each one, adding ice packs is critical?

Update:
Usage: carry cooked food (chicken, beef, rice, pasta) etc straight out of my fridge to the way to the office. My understanding is that such bags can't keep it in proper temperature for hours but should be able to keep it in a very good temperature at least till I get to somewhere I can put the lunchbox in a fridge. Also has to be small and easy to carry