The RB-12 meets every expectation of an Ironman tireñña practical choice that delivers affordability and dependability without sacrificing for either. Its symmetric, five-rib tread design creates a larger footprint that increases stability and performance. Combine that with a noise-reducing design and a M+S rating, and the RB-12 becomes the tire of choice for a ride thatís all about comfort, in all conditions, all the time.