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Shampoo bars—hair cleanser in bar soap form—are the latest trend in hair care products. Usually made of natural ingredients to promote hair health, they’re also easier on the environment and great for travel. Here are five reasons to make the switch from bottle to bar.

Reduction of Plastics

Currently, about nine million tons of plastic get thrown into the ocean annually, which breaks down to one garbage truck full of plastic being dumped into the sea every minute. Shampoo bars cut out the need for plastic bottles, and most come wrapped in recycled paper or in paper boxes. They’re also convenient for traveling—just pop them in a metal tin available for that purpose.

No Worries About TSA Limits

A traveler’s nightmare is having TSA agents raid your bag, asking if you’re over the 3.4-liquid-ounces limit, or worse, opening your suitcase after a flight and finding that your shampoo bottles leaked all over your favorite outfit. Shampoo bars eliminate both scenarios, as TSA isn’t going to take soap that’s in bar form and a shampoo bar won’t ruin your clothes. It might make them smell good, though.

Concentrated to Last Longer

Most shampoos are 80-percent water and conditioners can be even more—up to 95-percent water. Why pay for water when you can add it in yourself? Shampoo bars are megaconcentrated and generally last longer than bottled versions. On average, a shampoo bar will outlast two to three bottles of liquid shampoo, meaning you save money and extra trips to the store.

Cruelty Free and All Natural

Many brands that produce shampoo bars are striving to protect the oceans, wildlife, and ecosystems that are being affected by the mass production of chemical-laden products in the beauty industry. Many traditional bottled shampoos are filled with preservatives and chemicals that can strip hair of its natural oils and leave your scalp feeling dry. Oftentimes, these chemicals are not found in shampoo bars. Many bars contain essential oils and natural ingredients and are cruelty free. Another plus? Many shampoo bars are free of palm oil, an ingredient linked to deforestation and habitat degradation.

Where to Find Them