Ricta Clouds White 78a Skateboard Wheels (57 mm) Smooth-rolling and fast 78A soft urethane with a solid 78D core. Clouds make even the roughest of surfaces feel like smooth warehouse floors. Modern-shaped and not heavy or bulky. Perfect for filming and just cruising. Smooth-rolling and fast 78A soft urethane with a solid 78D core. Clouds make even the roughest of surfaces feel like smooth warehouse floors. Modern-shaped and not heavy or bulky. Perfect for filming and just cruising.