The aftermarket wheel was smaller and maybe lighter than the factory wheel. And more comfortable with the cushioning. The smaller size also gave me more elbow room inside the car. And the new wheel was more electrically reliable than the original, with the simpler switch and wiring. Precision CNC manufactured to extremely high tolerances. High strength specially enhanced 7075 T651 aluminium alloy. Computer aided ‘Ultra light’ design gives the maximum reduction of unsprung weight at the rear wheel, to give maximum power transfer. Renthal rear chainwheels are 33% lighter than steel. Only available in hard anodised (bronze colour - very hard,.highly wear resistant, substantially increased life).