A good question to begin with. You can learn alot by taking the time to read so please do so and click here. In a nutshell, wheels can actually expand and contract up to 10% of its original diameter under extreme conditions (such as in F1). A true quality wheel will enable this “flexing” to occur precisely. Poor quality wheels either aren’t able to achieve this or do not achieve it in an efficient, desired manner. A hard, callous wheel is not desirable as it does little to absorb nor relieve any unnecessary stress/tension that can channel its way to the chassis and components of a vehicle leading to unwanted results in performance and comfort. A quality wheel is not only one that is strong or light, but one that has balanced strength and weight characteristics that help to ease this flex/tension properly. This is the goal of MAT. This MAT wheel forming process is unique and considered to be of the highest technology improving the material properties of the wheel and its overall performance characteristics. MAT enables production of an accurate and balanced combination of weight, strength and rigidity. Too much of one characteristic doesn’t necessarily produce better results. This balance is what Enkei’s high-performance wheel production methods are centered around. (There’s a good amount of information on the Enkei North America website. It might not be the most stylish site, but it definitely matches Enkei’s engineering personality.)