Hoka One One | Shoes | Nib Blue Hoka Challenger Atr 7 。Hoka One One NIB Men\'s Challenger 7 Ultramarine-Oceanic Trail running shoe. Size 10D Street-approved. Trail tested. Built at the intersection of road and trail, the Challenger 7 has been completely reimagined from the ground up. Combining a simplified mesh upper with a soft new foam, Hoka increased the stack height for a plusher feel and added proprietary rubber to the bottom unit, along with a reimagined outsole design for the best all-terrain ride yet Inspired by gravel tires, they cued up smaller, tightly spaced lugs in center and larger, more aggressive lugs at the perimeter designed for improved traction on uneven terrain.