When you hit the trails in Smartwool's PhD® Run Ultra Light Low Cut socks, the socks are the only thing that should be low. Expectations and elevations should be high. Because this sock was made to help you push boundaries. Smartwool's PhD® Indestructawool technology enhances durability, while Shred Shield technology reduces wear from toe. Smartwool includes body-mapped mesh zones for additional breathability and Virtually Seamless toe for enhanced comfort. We suggest you take it and run with it.