Vulcan Roller Motion - FrontOverview The shape of the Vulcan Roller Motion allows the farrier to achieve a better fit more quickly because the shoe is designed to fit around the coffin bone with few alterations, meaning the widest part of the shoe aligns with the widest part of the foot quite well right out of the box. Design Features Concave Section with Deep Fullering Includes a higher inner rim for easier medial lateral movements Versatile Nail Hole Pattern Convex radius