I’m a grown man, and zippers can still be tough. Lining up the slider perfectly with the very bottom of a zipper is the simplest thing in the world. . .until something goes wrong. Maybe I pull carelessly and the teeth get off by a rung. Maybe my fingers are frozen and the task becomes akin to threading a needle. Maybe I yank too hard and the whole thing just breaks.

*@&#!!

Apparel maker Under Armour has a solution. Starting this November, its clothing will include the Magzip, an ingenious zipper that magnetically clasps automatically and still provides just enough leverage for you to zip up one-handed if you need to. Trying out a sample the company sent me, I’m amazed each and every time it works. The Magzip a testament to mechanical ingenuity in the electronic age.

But the product wasn’t originally conceived for convenience. As engineer Scott Peters watched his uncle develop myotonic dystrophy, a condition notorious for attacking the strength and coordination of one’s appendages, he saw first-hand how manipulating buttons can impossible task, and even aligning the box and pin of a zipper can become daunting.

“My mom [an occupational therapist] and I got talking how to help him, and i jumped right in–‘I think i could come up with a better zipper than what the rest of the world has used for 100 years,'” Peters tells Co.Design. “So we put a few magnets on a zipper, and of course that didn’t work so well.”

But Peters believed in the idea, playing with magnets on zippers for months before he caught a break. Sitting around a campfire one evening, his idea attracted the attention of a neighbor who happened to be an accomplished mechanical engineer and designer in his own rite. Together, they took on the problem in the only way it could be–constant iteration. The eureka moment of a magnetic zipper was crucial. But the exact millimeter grooves making the process practical would require painstaking nuance.

“Magnets in and of themselves won’t work. They’ll drive components together, but you have issues of alignment, issues of holding things together without popping out–and pulling them apart can be a nightmare,” Peters explains. “We had to figure out the combination of mechanical design so it self-aligns and easily locks itself in place, enabling you to zip with one hand.”