As travel looks to make its return following the shutdowns at the start of the Covid-19 pandemic, there’s one topic that’s top of mind for both the industry and consumers: sustainability. As travelers look to return to the skies or hit the roads, and airlines and other operators look to transport or host them, many are looking for ways to ensure their journeys are responsible.

Actor, producer and director Adrian Grenier is no different. As a self-proclaimed professional traveler and activist for environmental causes, “Entourage,” “The Devil Wears Prada” and “Clickbait” star Grenier looks to make sustainable decisions when it comes to going on vacation or traveling for work.

In a new partnership with Booking.com, Grenier is helping to highlight sustainable travel options for everyone. According to Booking.com, 66% of Americans want to stay in sustainable accommodation in the upcoming year. With the introduction of Booking.com’s Travel Sustainable badge, travelers can easily find out what properties in a given destination are committed to offering sustainable practices.

“It’s like a gluten-free label,” Grenier told CNN Underscored. “When you’re buying stuff, you want to know it has certain characteristics that are not harmful to you or to the planet. And to have a badge that’s easy to see and know that when you click on the purchase, they’ve gone through the trouble of making sure that destination is doing what they can to be more environmentally responsible.”

Each of the properties that’s available for booking — whether it’s a hotel, B&B, holiday home or anything else — and has earned the Travel Sustainable badge will display that acknowledgment when booking. The requirements for obtaining the badge vary by property, but will be awarded to any property that “has implemented a combination of sustainable practices that meet the requisite impact threshold for their destination,” according to Booking.com. The site has collaborated with industry experts to identify the most impactful practices in five key areas: waste, energy and greenhouse gases, water, supporting local communities and protecting nature. The practices will then be assessed in a calculation to determine if a property is eligible for the badge.

For example, Mr. C Miami — Coconut Grove has the badge as it offers energy-efficient lighting, limits single-use plastics, takes steps to reduce food waste and more.

“During our repose, we’ve all had a chance to reconsider our place in the world and how we want to do things differently going forward,” Grenier said. “I’ve been encouraging more sustainable mindfulness.”

When it comes to his travels, Grenier tries also to do his part by taking as little with him as possible. By getting everything into a carry-on bag, he tries to travel light — but never without five products that make every trip with him.

Whether Grenier is visiting his favorite European city Copenhagen or his favorite vacation destination Ibiza, here are the five travel products he doesn’t leave home without.

A good toiletry bag

A quality toiletry bag is essential for keeping your belongings organized. If you’re planning to take just a carry-on bag during your travels, finding a toiletry bag with plenty of compartments that’s also compact enough to fit in that bag is key.

But it’s not only the bag itself, but what’s in it as well. “I’ve made a lot of effort to reduce the plastics from my toiletry bag,” Grenier said.

Here are some toiletry bags we like best.

Designed to fit everything

The Away Large Toiletry Bag is a solid option if you're looking for a case to fit all of your goods. The case itself zippers shut and also has an interior zip pocket for smaller items. It's nylon on the exterior and it also water resistant.

Spill-proof storage for your toiletries

This toiletry bag comes not only with a spill-proof design, but also has a mirror built-in so you can touch up your makeup while you're on the go. There's plenty of storage and it comes in two colors: beige or black.

A fanny pack

If you’ve never traveled with a fanny pack before, it could be the perfect addition to your outfit. For Grenier, it’s all about the storage.

“You’ve got to have access to all your stuff when you’re walking through the airport or sitting on the plane,” he said.

Whether you’re looking to take a fanny pack with you on a plane in order to have your passport and cellphone close to you at all times or if you’re looking to take it with you when you get to your destination, a fanny pack is a solid travel investment.

Here are some of our favorites.

Secure your belongings on the go

Whether you're walking through the airport or walking down the street in New York, you'll want somewhere to store some of your belongings. It has a shoulder drop as well, allowing you to change the style and fit at any time.

Good for hiking, running or exploring

If you're looking for a versatile bag, this is a solid choice. Each of the compartments — two large pockets and two smaller front outside pockets — has a zipper closure. Additionally, it's water-resistant if you're eyeing it for use outdoors.

A comb or brush

Let’s face it: Travel isn’t always glamorous, especially for our skin, body and even our hair. For that reason, Grenier says he always travels with a comb or brush in his bag in order to keep his locks looking good.

Brushes and combs come in all sizes, making it easy to fit one in your carry-on bag, no matter what size that bag is. Better yet, put your comb in your fanny pack for grooming on the go, no matter where you are.

Here are some combs that could be the perfect travel companion.

Polished, anti-static comb

With more than 3,500 5-star reviews, this comb made from natural green sandalwood is a great product to take with you on the go. It doesn't snag your hair and won't cause static.

Tangle-free hair

With an ergonomic palm-shaped designed, this brush was made for travelers. The brush has long teeth to detangle hair and short teeth to smooth the hair cuticle.

An external battery

Keeping your devices charged while you’re traveling is key to a well-connected and seamless travel experience. Between showing your boarding pass, following a map for directions and keeping your followers updated on social media, your electronics’ batteries take a beating while you’re traveling.

Here are some of the top portable chargers we’ve tested.

The best overall portable charger

In our testing, we dubbed this Anker portable charger the best on the market. Where it really shines is with its capacity, which can fully charge an iPhone 11 more than two times.

The most portable charger

This is a great option for charging your things while traveling if you've not got much space. With a Lightning port as well as a USB Type A port, you have a couple of charging options.

A good book

Grenier doesn’t hit the road without a book in his bag — or in his hand. “There’s something nice about a physical book — especially when traveling,” he said.

Grab one of these books for your next flight.

A new release

This novel by bestselling author Amor Towles takes place in the 1950s when Emmett Watson returns home from a juvenile work farm. However, his plans change when two work farm friends hide in the back of the warden's car and take him in the opposite direction.

A travel classic

Cheryl Strayed's memoir of her solo Pacific Crest Trail hike when she was 22 will make you want to get back out there on your next adventure.

Looking for a travel credit card? Find out which cards CNN Underscored chose as our best travel credit cards of 2021.