Women in New York City and San Francisco are obsessed with these comfortable flats made from recycled water bottles - here's what they feel like

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• Whether you've seen its ads on social media or have admired its flats on your co-worker, San Francisco shoe startup Rothy's seems to be everywhere.
• Rothy's flats are more than just a pretty work shoe. Its rounded flats ($125), pointed flats ($145), and loafers ($165) are made from 100% post-consumer plastic water bottles and other recycled materials, are machine-washable, and feel light and flexible on your feet.
• Rothy's innovative approach results in a comfortable, stylish, and sustainable shoe that you'll love wearing.

Despite my mother's frequent pleas to wear heels more often ("They'll make your legs look longer!" "They'll force you to stand up straighter!"), I've always been more of a flats girl. I've encountered few pairs of heels I can walk around in for more than an afternoon, but many pairs of flats I wouldn't mind living in.

Stephen "Hawthy" Hawthornwaite and Roth Martin realized such all-day comfort is important to women, but so is style, and increasingly, sustainability. Combining their names and these three priorities, they created Rothy's in 2016.

In two short years, Rothy's flats have become the favorite work shoe for women in the exact two hubs that Allbirds, another San Francisco-based shoe startup known for innovations in comfort, style, and sustainability, has also seduced: the Bay Area and New York City.

Though both are trendy metropolitan areas, they're wildly different in pace of life and professional culture. That Rothy's is popular among both markets speaks to its quality, versatility, and understanding that geographic and cultural differences notwithstanding, women just want a pair of quality flats in their closet.

Rothy's makes three types of shoes: The Flat ($125), The Point ($145), and The Loafer ($165). These three classic silhouettes have a few modern twists, which speak directly to the conscious consumer who is more critical than ever of where her purchases come from and how they represent her personal style and values.

The unique upper knits of the shoes are made from 100% post-consumer plastic water bottles, which are hot washed, sterilized, then fused into a fiber that is then knit into yarn. The company has repurposed 12 million water bottles (and counting) and joins the growing movement of brands also using recycled plastic to make sneakers, leggings, and even watch bands.

The use of sustainable materials doesn't stop there. The insoles contain recycled foam, while the rubber soles are carbon-free. The adhesives used are non-toxic and vegan. The packaging the shoes come in is made from post-consumer recycled materials and is biodegradable.

Because of how they're made, Rothy's shoes have a distinctive feel and functional advantages that other flats don't. The seamless construction means there are no uncomfortably hard seams or edges (and is also less wasteful because this 3D process knits to the exact size of each pair and doesn't require any cutting), and the shoes are very light and flexible. They're moisture-wicking, fighting against sweat and rain, regardless of the season. They're also easy to maintain since they're machine-washable.

When it comes to style, you have plenty of options to choose from. There are more than 20 styles each of The Flat and The Point and eight styles of The Loafer, from the simple Black Flat and casual weekend essential Taupe Heather Loafer to the made-for-summer Marigold and sophisticated Lapis Python Point.

We tried four different pairs ourselves to see if they lived up to the brand's promises. Though there are other flats we favor in terms of perfect comfort, we did love the look and eco-friendly construction and would overall recommend Rothy's to anyone looking to invest in a pair of stylish, reliable flats.

Sally Kaplan, Insider Picks editor: The Point in Flax Birdseye, $145

I am extremely picky about flats, mostly because it's hard to find ones that are the perfect storm of cute, affordable, and comfortable. This pair almost meets all three of those criteria, with the exception of the price being slightly over what I'd normally pay. That said, they are quickly becoming my go-to pair for work. I won't call them the most comfortable flats in the world (that title is reserved for the Everlane Day Glove), but they are exceptionally easy to commute in and I don't pray for the moment I can take them off every time I wear them.

The one thing I will say is that if you have wide feet, the pointy-toe style is not for you. I'd go for the loafers in that case. I don't have wide feet but they're not narrow either - and these fit perfectly for me. My pinky toe rubbed against the seam a little bit, but not enough to cause a blister, so I'd call that a win.

Overall, the lack of break-in period (for me, at least) and the little bit of stretch afforded by the knit upper are the two features I've loved most and I'd definitely recommend these to anyone looking for a stylish work flat.

Connie Chen, Insider Picks reporter: The Point in Emerald, $145

I've noticed quite a few women wearing Rothy's because of their signature blue stitching and sleek look, so I was excited to finally give them a try. I love pointed flats, especially because I have small feet for my height and the shape helps elongate my feet, so right off the bat I liked Rothy's well-designed take on the style. Work flats tend towards neutral colors, but I had plenty of pretty and jewel-toned options to choose from, including this deep Emerald green.

When I first slipped my foot in, it almost felt like the flats would be too big, but they turned out to hug my feet perfectly. Though they are designed to have a slight give, the company does recommend ordering half a size up if you have wide feet. As with many flats, there was a slight break-in period, but the plus is that they were very light on my feet the whole time, making the process a bit more comfortable.

Plastic water bottles don't initially sound like they would translate well into a good pair of flats, so I was impressed with how well Rothy's did pull it off.

Malarie Gokey, Insider Picks guides editor: The Loafer in Lollipop, $165

Rothy's Lollipop Loafers almost feel like slippers, but they look much nicer. I really like that they're made out of recycled plastic - it's something anyone who is eco-conscious will appreciate.

I don't typically wear flats, but these are perfect for throwing on when I need to run errands around the neighborhood. They're comfortable, breathable, and flexible enough for wearing in the summer. Rothy's loafers aren't quite as supportive or comfortable as Everlane's Day Glove flats, so I wouldn't wear them if you're going on a really long walk - especially if you're in a city. However, I think they're perfect for office wear.

Personally, I'd love the exact same pair of shoes with a 1 1/2- or 2-inch heel for a bit more impact absorption and height, but that's me. If you love flats and you don't plan to walk more than 3 miles any given day, Rothy's are a wonderful, eco-friendly, stylish choice.

Ellen Hoffman, Insider Picks senior editor: The Point in Red Camo, $145

Some women really love pointed-toed shoes, and others really really don't. I fall in the former camp since they help elongate my 5'3" frame and since, aesthetically, I'm drawn to the silhouette. I was attracted to The Point flat in particular because the style looked sleek and professional for work, and importantly, promised seamless comfort and support in the form of a 3D knit upper and removable insole.

The Point was feather-light and very breathable, so walking around Manhattan in 90-degree weather was never a hindrance. I was able to wear the shoe right out of the box with virtually no break-in period, although I suggest opting for The Flat or The Loafer if shoe width is concern since The Point did squish my right foot's toes together a bit too tightly for my liking.

I got the "red camo" color for something different since I usually play it safe with black or another neutral, but there are 22 other colors to choose from should you want something not quite as bold.

Mara Leighton, Insider Picks reporter: The Point in Red Camo, $145

I love Rothy's sustainable ethos - and for the most part, I loved the shoe in reality, too. But I also live a bit more than a mile away from the subway station I take every morning and night, so my shoes need to be disproportionately comfortable. For this, the Rothy's were a tad narrow for all-day comfort in my right foot, though this isn't the first time that has been an issue. I have average to narrow feet, so if you have wide feet I could see this being an issue for The Point style.

In terms of aesthetics, they're some of my favorite flats; the red camo print is vibrant and unique, and the pointed toe elevates a blazer and jeans. And for other areas of comfort, the Rothy's also deliver with machine-washability, removable insole, and a knit upper for seamless bending and breathability.

All in all, I really liked the Rothy's, and I'll continue to wear them. But if you're going to be power walking a couple miles in them daily, you might want to save these to change into once you get to the office. -Mara Leighton

Ranging from $125 to $165 a pair, Rothy's are a step up from the average pair of flats, not only in price, but also in quality, style, and ethos. Shoppers are realizing they don't have to compromise on any of the criteria they care about, and Rothy's is a prime example of how to live up to those high expectations.

Shop flats and loafers at Rothy's here