Allbirds Tree Runner - a thoughtful shoe that's light and breezy. The Tree Runners offer cooling comfort to keep things light and airy. From sunlit strolls to adventurous outings, the Tree Runner is an ideal companion. They're breathable, lightweight, and can be worn sockless, making them the best travel shoe. Maybe we were going out on a limb when we thought to make shoes out of trees. But thanks to magical sustainably harvested eucalyptus tree fiber, our Tree material is breathable and silky-smooth, complete with a cooling effect to keep things breezy. It's naturally-derived and renewable, too, meaning it's much friendlier to the environment than traditional shoe stuff. Features & Design: lightweight and breezy, flexibly conforms to your movements, help your feet stay cool, silky-smooth material, so soft you can wear sockless, minimizes odor, machine washable, low carbon footprint, padded insole, tree upper, bio-based eyelets, recycled laces, lightweight sole, Allbirds Women's Tree Sneakers, Marine Blue, Size 9