A hat made from Rambouillet wool is a perfectly nice hat. The fiber, shorn from a Rambouillet sheep, is fine and soft. Not at all scratchy. “They call it the American merino,” says Dan Widmaier, the founder of Bolt Threads, a biotech company that grows synthetic spider silk from yeast.

Earlier this year, Bolt bought Best Made Company, a high-design outdoor brand that makes hand painted axes and fancy toolboxes. It was an unexpected move—what did a biotech company want with a lifestyle brand, anyway? It turns out, Bolt wanted to make a new kind of wool hat.

For its first joint product, the companies are launching a limited edition version of Best Made Company’s Cap of Courage, a $198 striped beanie that’s made by combining Bolt’s Microsilk and Rambouillet wool. More than anything, the run of 100 caps is a proof of concept. It’s a way to show that the elusive science behind crafting synthetic spider's silk is no longer elusive. In fact, it’s scalable enough that customers can walk into a store, pick up a spider silk hat, and wear it on their walk home.

Home-Brewed Silk

Five years ago that would’ve been unthinkable. Spider silk is an ace of a material. It’s soft, flexible, and strong as steel. But it’s also a terror to produce en mass. Spiders, no surprise, tend to cannibalize each other before they crank out enough silk to be useful. Scientists tried BioSteel goats, animals that are genetically modified to produce the filament of a Golden Orb spider, but that proved untenable, too.

Bolt Threads

For more than a decade, Widmaier has worked on solving the problem by growing proteins that mimic spider silk in yeast. “It’s been one of those things that’s often talked about as the next big thing but never actually getting out in the hands of consumers,” Widmaier says. And this year, he and his team of biologists got it right.

In the spring, Bolt released its first product, a $314 tie made entirely from synthetic spider silk. The cap is its second official good, and Widmaier says this is just the beginning of what Bolt hopes to do with grown materials. “We think the same process can make pretty much any protein based material nature has evolved,” he says.

In the case of spider silk, Bolt designed its fiber to mimic dragline silk, the flexible, kevlar-strong filament that a spider extrudes when it rappels. Analyze Bolt’s fiber and natural silk, Widmaier says, and you’d see the same molecular makeup. “All the things you observe scientifically are the same,” he says. “We just make it with a different process.”