French startup Smart & Blue believes that we don’t realize how much water we use in the shower. And so it has made a product that tells us just how much water is running down the drain while we’re singing a little too long.

The Hydrao Loop measures water usage in the shower and lets you know how much you’ve used by changing color. If the indicator stays blue, you’ve only used a few gallons of water, which is considered acceptable. But if it turns green, yellow, and finally red, then you’re wasting water. (You can customize the colors as you wish).

The Hydrao comes with an app that tells you how much water your family is using and how that changes over time.

The Grenoble, France-based company also designed the Hydrao Drop for overhead showers. Both versions can help reduce the amount of water you use, and the diffused light can also create a happier ambience for you while you’re scrubbing. The Hydrao products are designed to work with existing showers.

The whole point is to save water. Most of us use around seven to 10 gallons of water per shower. Of course, if Hydrao makes your shower environment too nice, you might want to stay in there even longer.

Here’s a video of how it looks in action. You can preorder it for $100, and it will be available in about six months.

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