Under Armour Allsport Socks. The Under Armour All-Sport Cushion Sock features welt top construction that provides comfort and fit. 1×1 rib, knit-in arch support reduces foot fatigue while increasing blood circulation. Built-in vents maximize foot ventilation. Fully reciprocated toe construction with flat toe seam provide a perfect fit, while the full-cushion footbed adds maximum shock absorption and protection.