The running sock that acts as a statement of intent for your run Never slip - The pattern at the arch triggers sensory receptors to prime your feet for the run while Swiss engineering keeps the sock firmly in place for performance standards that don't slip. Stay in balance - Made using 94% recycled polyamide, it features technical mesh paneling keep temperature in perfect balance. Cooling when things heat up, warm enough that you won't get cold feetwhatever you're about to take on. Protection, anywhere - The new edition of the Performance High Sock offers lightweight protection that has you covered for everything from a chilly morning commuter dash to an epic off-road adventure | On Men's Performance High Sock in Black/Shadow, Size: 40-41. Cold-weather running, supportive, balancing Running, Road Running, Trail Running, Marathon, Competition, Track And Field. Performance Outdoor | Polyamide