Climbers Craig and Cyndy DeMartino live in Loveland, Colorado, at the mouth of Big Thompson Canyon. If you don’t know Craig’s incredible story, he lost his lower right left after surviving a 110-foot ground fall in 2002. These days, he has a collection of legs, including a walking one and a climbing one. None are perfect, but he has become a master of adaptation, working with the tools at hand. At age 54, Craig climbs 5.12+, and in 2008 with Hans Florine made the first amputee ascent of the Nose in a day.

On the other side of the world, as DeMartino was reckoning with his new post-accident reality, a 10-year-old boy was growing up, one of six million people in the industrial city of Fuzhou, China, a manufacturing hub for Nike, Adidas, and Fila. Kai Lin loved to draw. He’d lock himself in his bedroom and pretend he was doing homework, sitting on a secret passion that was not seen as a viable career in an exploding industrial economy. “My family wanted me to be studious. Drawing was my way of expressing myself, without having to think about constraints or limitations,” he says. “It was my way of escaping the reality.”

Kai Lin, a Chinese man, sits on the edge of a crash pad at a climbing gym.

Kai Lin partnered with Craig DeMartino to change the world of climbing prosthetics. 

When Lin’s family emigrated to the United States when he was 15, the constraints fell away. Suddenly, he could be an artist, although adapting to a new culture meant watching carefully, a habit that became ingrained. “It’s almost second nature for me to ask, ‘What is that person thinking?’ Or ‘What does that person need? How can I make it better?’” says Lin, who studied industrial design at the Pratt Institute and today makes his living as an industrial designer in Brooklyn. So when he was faced with the problem of designing a climbing tool that will substitute for the 26 bones, 33 joints, and 100-plus muscles, tendons, and ligaments in the human foot, Lin set to work in his persistent way.

Prosthetic climbing foot sits on a wooden table in a workshop. Bottom of the foot is black and curved like a foot. The ankle joint is blue with a bolt at the hinge.

Kai Lin got inspired to make the KLIPPA while watching a video of mountain goats and wondering if he could design a limb that allowed humans to move like them. 

In 2014, Lin’s mountain-goat inspired prosthetic leg, KLIPPA (Swedish for “cliff ”), was a US national finalist in the James Dyson Award. The internet lapped him up—a smart, young design student conceives a nature-inspired piece of über-tech that could help US veterans climb their way through trauma and PTSD! Some filmmakers introduced him to DeMartino; Lin made headlines, did interviews, but the project languished. He needed money to build a functional prototype, he needed collaborators to test it, and after finishing school, he was busy working his day job as an industrial designer. Still, the feedback he was getting from adaptive climbers, family members, and prosthetists kept him tinkering, knowing his design could make a huge difference in the lives of a small group of underserved people. When Arc’teryx, looking for inspiring problem-solvers operating outside their silos of expertise, offered Lin the use of their 3D printer and to reconnect him with DeMartino, the project relaunched.

Parts to create a prosthetic leg lie on a dirty white background: a hammer, tin box with plastic wrappers, a climbing shoe, screws, plastic parts, wrenches, a ruler, and a spring among other technical pieces.

The KLIPPA is made from both complex materials and simple tools. 

DeMartino first tested the KLIPPA in Indian Creek, Utah. Though the early prototypes didn’t hold up to the rigors of straight-in crack climbing, he and Lin kept at it. They had much better success with the next round, with DeMartino climbing vertical 5.10 and 5.11 face routes on the Crystal Wall in the Poudre Canyon near his home in Colorado. The KLIPPA gave him the mobility, sensitivity, articulation, and control he needed, and just like that he was clipping the anchors on the wall’s technical climbs. “[The Klippa] is now being remade to test more,” says DeMartino. “It’s a process, but one that’s going the right way.”

Concludes Lin, “I can design specific things that will make people’s lives better through the objects they interact with on a daily basis. That’s what I’m good at. And that’s something I can do.”

Read the full story by Lisa Richardson.

Black text reads Arc'teryx below a black skeleton of an animal.