Answer: In most cases, scratches on glass are distributed irregularly. A piece of glass may have one scratch or several. Even if there are multiple scratches, it is not necessary repairing the entire piece of glass because that solution is not so cost-effective as replacing. Plus, scratches differ in depth. Anyway, such unit of measurement as square meter is false. We can only introduce the depth of cut left by another piece of glass or by sand. For a 5 cm long general scratch (left by another piece of glass or by sand), a kit (1 coarse grinding sheet, 1 fine grinding sheet, and 1 polishing pad)can repair more than 10 scratch point (each point is roughly priced at RMB 2.7). However, its ability to repair serious scratches like burning by spot welding slag cannot be estimated because both severity of scratches and the acceptance requirement are unknown.