WHEEL PROFILE Medium - Your classic wheel shape, versatile all-around wheel for street/park skating. SURFACE Smooth - Smooth wheels come with a shiny coating on the riding surface that feels grippy at first, but wears away quickly. KEY FEATURES Formula Four Urethane - Unmatched abrasion resistance for fewer flat spots. More controllable grip. Lasting speed no matter the terrain. Smooth anti-slick slide and a longer lasting size and shape. WHEEL SHAPE Radial Shape - Round edge design for control, speed and a responsive slide. DUROMETER 99a - Offers more grip than harder wheels and more slide than softer wheels. Great for slick surfaces when you want more control. SPECS SIZE 53.5MM 57.5MM DIAMETER (MM): 53.5 57.5 WIDTH (MM): 33.7 36.5 RIDING SURFACE (MM): 20.0 23.5