About Koriboshi

Hi, we're Alan and Linna — and we're obsessed with saunas. What started as a post-climb ritual at our local gym sauna quickly became a non-negotiable part of our lives.

For Alan, the sauna became something even more personal. After spending over a decade designing products at some of the world's most demanding companies — Apple, LinkedIn, Meta, and Bloomberg — he was used to obsessing over details and building things people love. But it was losing his dad to cancer that truly reoriented everything. It made him question how he was spending his time, what he was building, and whether it actually mattered.

Through that grief, he found himself drawn to a deeper question: how do we actually take care of ourselves? The sauna became part of the answer. But the more time he spent in the heat, the more one nagging problem kept coming up: his head would overheat before the rest of his body was done. He tried every sauna hat out there. Too rough. Too hot. Impossible to wash. Nothing felt right. During a trip to Asia, we noticed people using towels to protect their heads.

Then in Japan, we found something closer — beautifully crafted cotton hats, soft and simple. That was the spark. As a product designer, Alan couldn't let it go. He knew he could make something better — something that actually fit into the ritual, not just tolerated it. 

This inspired us to create Koriboshi   —    Kori = Ice    Boshi = Hat

Japanese-inspired, obsessively designed, made for real sauna people. Soft, breathable, easy to wash, and built to make every session a little better.