Have you ever notice the dent in the side of a milk bottle wondered what purpose it serves? There are in fact two purposes of the dent that are very beneficial.

Firstly, the dent expands outward in case there is excess gas in the milk jug, warning the consumer that the milk has spoiled.

Secondly, the dent is there to absorb any shock if it falls. It prevents the jug from exploding in case it drops.