When you want the absolute minimum between your feet and your ski boot for a more technical fit, you need our PhD® Ski Ultra Light socks. Smartwool's thinnest, most lightweight ski socks equip you with their Indestructawool™ technology for enhanced durability; their 4 Degree™ elite fit system for a dialed-in, performance-oriented fit; and their Shred Shield™ technology for reduced wear from toes. They are designed with a wider welt to help ensure all-day comfort and body-mapped mesh zones help keep things breathable. All in all, these are the socks you want in your technical ski boots as you head for a day full of skiing.