Have you ever noticed the tiny colored square at the base of your toothpaste tube? 

The square at the bottom of the package is usually red, black, blue, green, or yellow. Some believe it's a secret code to tell consumers about the levels of toxicity in the product, but that's not true!

It turns out the little squares are called "eye marks" and are similar to the ones used at printers. 

Each box's placement and color is detected by a machine's light beam sensors and tells it where to cut and fold the tube. As a result, each tube is prepared in record time.

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