Smartwool designs base layers, baseball caps, leggings—basically every apparel item you could want for an active day out in nature. But what the Colorado brand is really known for is its socks. Super cozy, super quality, Merino wool socks.

As of Earth Day on April 22, Smartwool will be recycling your old socks—no matter what the brand.

Socks are the most thrown-away clothing items there is. After all, who would want them? To help close the recycling gap and provide a home for those past-their-best socks, Smartwool has come up with a plan.