With a superb level 5 thermal rating, these merino wool-rich UpHill Sport “OPS” Tactical 4-Layer M5 Socks are designed using a Drytech structure of layered merino and polypropylene that provides excellent warmth, moisture control, and breathability in even heavy conditions, but with a medium thickness. The Uphill Sport OPS sock is inspired by the needs of those who take on multiple days of trekking, with overnight stays and changing conditions. The multilayered structure transfers moisture away from the skin and can adapt as conditions alter, able to dry quickly overnight and without absorbing sweat and smell. Uphill Sport ethically only use Merino wool from mulesing-free sources. In a calf length with a lightly elasticised ribbed leg shaft, the sock’s foot section has a softly cushioned footbed, a fitted heel and supportive grip band in the arch, which adds comfort by stopping wrinkling by keeping the sock in place. Seamless toe sections help prevent blisters by eliminating seams that rub against your skin.