Fast laps through a few quick runs reward a precise boot feel, and the Halfdays Zero Cushion Ski Sock adds a non-cushioned, slim layer that leaves less bulk between foot and boot. The slim fit adds comfort without extra material in the boot. What Our Gearhead(R) Experts Are Saying:"On a spring day that started cold and turned warm by noon, my feet stayed comfortable from the first lap to the last because the sock breathed as the temperature climbed. I never stopped to change socks or loosen my boots."