The Allbirds Men's Tree Dashers are ultra-lightweight athletic-performance running shoes that are carbon neutral, as they're solely made via sustainable practices by only using natural and renewable materials. Not only are these athletic-performance running shoes designed for the maximum energy return possible, but they're also very durable, extremely breathable, super-comfortable, and very, very flexible, and they're also machine washable. Thanks to all of that, you get one of the best (if not the best) pair of sustainable running shoes that you can currently find available on the market, while simultaneously knowing that you're contributing to the overall reduction of greenhouse gas emissions.