Lightweight and very durable laterally stiff but vertically compliant - the Ksyrium SL sets a benchmark for aluminum road wheels. Patented ISM4D technology manufacturing process removes all excess material between each spoke hole while keeping the rim wall thick enough where spoke tension and stress is the highest. Fore technology creates a solid rim bed increasing stiffness and requiring no rim tape saving and additional 30g per wheel. Patented elliptical shaped double-butted spokes further reduce weight while making the wheel more responsive. New Infinity hub plaform: stiff axle durable bearings and new hub design guarantees wheel stability. Improved UST Road design means less friction better efficiency and grip a reduced risk of punctures. New rim bed shape makes it easier to mount and change tires