There are 4 levels of quality of solar silicon cells, called "Grade" - A, B, C, and D. Elements of different classes differ in their microstructure, which in turn affects their parameters and longevity. This type of solar panel is noncrystalline and can absorb up to forty times more solar radiation than monocrystalline silicon. Some module factories will have strict factory inspections during the production of photovoltaic modules, and divide the modules into A, B, C, and D grades according to. Solar panels are graded into categories A, B, C, and D based on their quality, and the cost differences between these grades can be significant.