The internet can't stop talking about these leggings made of recycled water bottles - and now I understand why

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• I own nearly 20 pairs of black leggings, but Girlfriend Collective's Classic High-Rise ($68) has been my all-time favorite for athleisure for two years now.
• Girlfriend Collective leggings are made from a flattering and helpful compression material that never pills. The well-placed seams elongate and slim.
• Each legging is made from 25 recycled water bottles, and the company prioritizes ethical and sustainable production, which they're transparent about.
• Girlfriend Collective leggings are sold at prices as low as $58, which is a steal in terms of industry standards and quality.

I own a lot of leggings. At the same time that I was running a little over 20 miles a week in a different pair every day, the athleisure trend hit - and I subsequently buried myself in black semi-spandex.

In that sea of options in my closet, there are a very select few that I really love - the ones that I know the feel of by memory and actually remember which company makes them so I can tell my friends when they ask. The pair that I love the most - thanks to their inventive, impossibly flattering seams; opaque, no-pill material; and thick holds-you-in-all-the-right-places fit - is from Seattle-based startup Girlfriend Collective.

You might know them best as the company that gave away its leggings for free over the internet in 2016. I first heard of them from that publicity stunt, when I paid $20 for shipping from Vietnam and $0 for a pair of classic high-rise leggings (now $68) while a senior in college.

A couple years later, those leggings are still my all-time favorite for athleisure. They're still dark black (even after many washes), the aforementioned seams follow the natural line of your body and slim as well as elongate legs, and the material and fit is still somewhat architectural, like a comfortable and slightly looser pair of Spanx. The no-pill material is slightly chicer than a normal athletic legging, so something about them feels "dressier" than my Lululemons, for example, which makes them easier to throw on for brunch or running errands.

I recently tried a new pair of the label's leggings that they sent over, and they're just as great as I remember. More than that, in comparison, my two-year-old pair still looks brand new. The no-pill claims are no joke.

Now, you can pick up the Classic Hi-Rise in five essential colors and fifteen limited colors - from electric lime to rose quartz. Sizes range from XXS to 6XL, and you can pick the length of the leg to ensure an optimal fit (from a 19.5" to 28.5" inseam).

Though the company encourages you to wear them for athleisure or exercise, their ability to transition to streetwear so well has made them my go-to athleisure staple. I've worn them during outdoor runs, but their thicker construction means that, as someone who prefers to run on a treadmill in a temperature-controlled gym and is prone to overheating, I don't recommend them for cardio or hot yoga (you could, but there are too many better options). Thanks to pairs like 2XU's Run Tights that operate like a porous second skin, I don't mind the limited versatility.

The secret to their incredibly flattering, Spanx-like fit is in the details: The core fabric used for them offers Girlfriend Collective's highest compression for muscle recovery after medium- to high-impact workouts, and enough softness to be comfortable. The leggings run true to size in my experience, and the company says the material will break in like your favorite pair of jeans the more you wear them. If you're worried about fit, use their Fit Guide here.

It would be one thing if Girlfriend Collective just made my favorite pair of flattering leggings, but they make them for much less than my other go-to pairs at $68 for a pair of classic high-rise. They're also ethically made and sustainably sourced.

Read more: I put the trendy leggings made from recycled fishing nets to the test in a hot yoga class - and yes, they're super breathable

Each pair of their leggings is created with 25 recycled water bottles (79% RPET), out of material made at Girlfriend Collective's Fair Trade facility in Taiwan. This saves 3.11 gallons of water and prevents 18.61 pounds of CO2.

Some "recycled" fabric production has been exploiting the loopholes by buying unused water bottles to churn a higher profit, but Girlfriend Collective's center is carefully monitored by the Taiwanese government recycling authority to make sure that's not the case for this company. Since you always have a choice of where you spend your money, even though some of us conveniently forget uncomfortable truths, Girlfriend Collective's factory uses no forced or child labor, mandates fair working hours and safe conditions, pays living wages, and allows workers to unionize.

I would love the fit of the leggings no matter what, but it's also an incentive knowing that my purchase reflects my values. Recycling is always a choice - even in clothing. It's nice to get the best product out there and simultaneously support a company that puts humane working conditions and sustainability first. Girlfriend Collective is one of my favorite no-compromise options.

All in all, I've spent a fair bit of time in leggings - and Girlfriend Collective's are made in a kinder, smarter way as well as delivering the most flattering fit at an unusually budget-friendly price. Win-win-win. If you're looking for a new pair, I highly recommend grabbing some for yourself before the bright, summertime limited colors are gone.

Check out Girlfriend Collective's leggings here

Buy the Classic Hi-Rise Leggings, available in 20 colors, $68