Toms founder Blake Mycoskie is known for pairing fashion and causes.

Hand-painted, colorful striped sunglasses. That’s the second chapter of Toms Shoes’ one-for-one business, revealed last week after months of mystery.

“With every pair purchased, Toms will give someone sight,” Toms founder Blake Mycoskie said.

Meaning that for every pair of sunglasses purchased, sight-saving medical treatment, prescription glasses or surgery will be donated to a person in need, a model that goes well beyond Toms’ original archetype of donating one pair of shoes for every pair purchased. Instead of offering glasses for glasses, “one person buys a pair of Toms glasses, and one person receives the eye care that he or she needs,” Toms’ website explains.

That website was swamped last Tuesday, the day the contents of mystery boxes distributed to 90 locations around the world were to be simultaneously opened to reveal Toms’ latest project. At the same time, Mycoskie made the official announcement in front of a crowd that organizers estimated at more than 1,000 at the California Heritage Museum in Santa Monica.

In less than 48 hours, some styles of the sunglasses had sold out on the website and in stores, and were on back order. “The demand has far exceeded our hopeful expectations,” according to a spokeswoman.

In less than five years, the young, shaggy-haired, rope-bracelet-wearing Mycoskie has turned into a visionary business leader who hobnobs with Bill Clinton and Nobel Peace Prize winner Desmond Tutu. Since 2006, he’s given away 1 million pairs of shoes in the United States, Argentina, Ethiopia and South Africa, working toward his goal of eradicating podoconiosis, a deforming foot disease caused by walking barefoot in silica-rich soil.

The shoes are sold at more than 500 stores nationwide and internationally, including at Nordstrom and Whole Foods, and many of Toms’ existing retailers bought the eyewear collection sight unseen.

“It’s fair to categorize [Toms] as a phenomenon,” said Pete Nordstrom, executive vice president and vice president of merchandising at Nordstrom, who attended one of 30 events Nordstrom hosted Tuesday at stores around the country to celebrate the rollout of the new product. “In my career, I’ve only been attached to two other things like this — Beanie Babies, which had a shelf life, but was more like a fad, and Uggs, which have proven to have longevity beyond what people imagined.”

This year to date, Toms is one of Nordstrom’s top-five selling shoe brands. “It’s grown from being an interesting item to being a big volume item that moves the needle in terms of business. When a Toms shipment comes in, we have a good day,”