Everlane will launch its first denim collection on Thursday at New York Fashion Week. According to the brand, by Tuesday, the wait list for the collection’s styles was over 40,000 — the largest yet for Everlane, which routinely releases styles that sell out.

To fete the launch, the direct-to-consumer brand will roll out “Denim Counter” pop-ups in New York City (September 7-10), Los Angeles (September 21-25) and Portland (October 20-21) over the next two months. (The brand currently has showrooms in San Francisco and New York City, where its offices are based, and plans to open its first permanent storefront in San Francisco’s Mission District later this year.)

2A style from Everlane’s new denim collection

Everlane is entering a crowded space with the collection, which is composed of five core silhouettes (high-rise skinny, mid-rise skinny and modern boyfriend for women; slim and straight for men) available in four different shades (black, white, light rinse and classic denim blue). However, it will have the buzzy benefit of being both ethically and sustainably made, two cornerstones of the “radically transparent” brand. To wit, the jeans are manufactured at Saitex, in Ho Chi Minh City, Vietnam, a Silver LEED certified factory that recycles 98 percent of its water, air dries every pair of jeans, relies on alternative energy for all its operations and eliminates waste wherever possible.

The styles, made of 11-ounce denim fabric sourced in Japan, will also sell for much lower than your average premium denim: $68, as opposed to $100-$500. That lower pricing system has been key to the brand’s success thus far. Its revenue in 2015 was estimated to have been around $35 million, and it’s believed to have more than doubled since then.

We spoke to Everlane’s founder Michael Preysman about why the uber-selective brand decided to take on denim, the challenges that come with producing sustainable denim and which of the company’s launches thus far have been mistakes.

MP head shot (1) (1) (1)Everlane founder Michael Preysman

Why launch denim next, and how long has it been in the works?
Everlane launched with a T-shirt in 2011, and in some ways, it made sense to launch denim next. But the truth is, denim is tricky — and a really dirty business. Factories take advantage of inadequate regulations, dumping toxins directly into our water and soil. We knew we wanted to find a partner that set incredibly high standards and had as little impact on the environment as possible, and it took us two years to find one. A little over a year ago, we found Saitex, which recycles 98 percent of its water and is a leader in sustainability.

At the same time, the denim market didn’t feel right for a long time; denim became stretchy and too expensive. We think the times are finally changing.

How did you get the price down to $68, if it’s sourced from premium Japanese denim and made sustainably?
When you buy a $200 pair of denim, it actually costs just $25 to make. Everlane was built on the idea that markups are too high and companies aren’t being transparent. In our case, we used the highest quality Japanese denim from our mill. It’s actually more expensive per yard than what luxury brands buy at the same mill.

The factory we chose has invested a lot upfront to create a cleaner, smarter factory. If you take the time to do this, you actually save money. It’s less water and less energy, and that translates to real dollars. In the end, our denim costs $31 to make. We transparently mark this up to $68 to account for materials, labor, duties and transports costs.

Everlane seems like a brand that could easily bill itself as unisex, which is in vogue right now. Do you have any plans to explore a unisex category?
We’ve explored the idea of unisex and often found that it’s better in theory than in practice. It’s hard to get the fits right for both. So instead, we encourage people to buy both men’s and women’s pieces, and often show styling that helps promote that.

1A style in Everlane’s new denim collection

Your company is known for buzzy launches that sell out quickly. What has been your most successful item launch to date?
We launched the Italian-made Day Heel this April, which garnered a 28,000 person wait list and continues to exceed our expectations. Our customers have told us that it’s the most comfortable heel they own and the only heel they can wear throughout their entire day.

What’s one launch that you consider a mistake, or that wasn’t as popular with customers?
We don’t consider any launches a mistake, since we’ve learned important lessons from each one, but there have been a few launches where we just haven’t seen a huge demand from our customers. For example, we launched an Everlane Mini children’s line a few years ago and ended up finding that most of our customers don’t have kids.