Crafted by a potter named M Sivasamy, this clay pot was designed to help keep produce cool for days.

He made a cylindrical pot made out of clay with a tap on one side and an outlet to pour water on the other side. A smaller pot fits inside the bigger one where you can place your vegetables which is then covered with a lid. The technology is simple — the water in the pot remains cool keeping the vegetables fresh and cool. - BetterIndia

For places with no or limited electricity, this could help immensely. Especially considering terracotta(earthenware) clay is almost used worldwide.

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