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Tree Upper
Silky And Breezy
Our proprietary knit feels silky smooth, breathable, and pleasantly cool thanks to eucalyptus tree fiber responsibly sourced from FSC® Certified forests.
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![](http://cdn.allbirds.com/image/upload/f_auto,q_auto,w_375/cms/2ECKBHp8QEro97mvhoov2O/0b5929f51c57d18405535bfd9c1d7779/TS-M-BTF-Mobile-02.png)
Low-Density Sole
Light On Your Feet
Expertly cushioned, our proprietary foam with an S-curve tread makes the lightest sole possible and mimics the anatomical flexibility of your feet.
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