Roadian At Pro Ra8 All Terrain. Improved Long service life Long Lasting Tread Life Excellent Off Road Performance Dual block Prevents gravel from being caught Staggered center rib Biting edges on off roads Micro grooves Improved traction performance Wide shoulder block Improved handling performance The Roadian AT Pro RA8 is comprised of a zig-zag sipe design and an open outside shoulder design to improve off-road performance with best-fit mud extraction and heat reduction. The sipe-in-groove design prevents pebbles from getting stuck and improves mud extraction performance, while the multi-sequence tread design on the center and shoulder deliver best-fit noise, wear and drainage performance. *By request/order.