At first glance, it might seem like a minor quirk of design or just a random byproduct of plastic molding, but that small, circular dent on the side or bottom of your milk jug is anything but arbitrary. In reality, it’s a clever and purposeful piece of engineering—an unassuming feature that plays a surprisingly big role in making your milk container functional, safe, and even eco-friendly. This little indentation, often overlooked, is a multitasker. It helps manage pressure changes caused by temperature shifts—think expanding gases when milk is transported or stored. It also acts as a shock absorber if the jug is accidentally dropped