Bought unique bento box…in summer, to prevent food poisoning, we have to be careful to carry food in the hot snd humid summer days and keep it in the cool temperature. People in Japan put umeboshi in the steamed rice to stimulate the appetite (from the salty and sour flavor) cos it has the effect of preventing food from rotting. Always popular ingredients of rice ball, Onigiri.
Well…back to the subject, my unique bento box’s has ice pack gel in the cover part and put freezer for 6hrs and use.
I am not sure if I will use for normal meal but definitely for salad lunch or our some fruits in the box!!