(Youtobe: https://youtu.be/t3-W9uLrq_k )
Honestly speaking, 9H is short for 9 hardness, and this is the original method to check the quality of pencils. This method was developed in early 1900?s by pencil manufacturers, they took 2pcs different pencils to scratch a coated surface and if they cause the same scratch damage to the coated surface, then these 2pcs pencils will be considered to be the same hardness. Reversely, people from coating industry adopted this manner today to measure the coating hardness by using variations of standardized pencil hardness.
While 9H hardness rating is supposed to be the highest among the pencil quality control.
Then ceramic coating now embellished with 9H to show its top quality enough to against scratch damage and do good protection for cars or boats paint. That is why many companies use 9H as marketing tool for their ceramic coating products.
However, since 9H is top quality control standard, why some people will claim the bad quality after application of nano ceramic coating to their cars? Simple, as nano ceramic coating is one kind of chemical formula products, and different component formulas will lead to different effect. Just take a simple example for your easy understanding. Let?s say one bottle Orange Juice. If people enjoy one real orange juice, they will be very satisfied to the taste, but if people have one orange juice mixed with more water, then the taste will be very terrible. That is same rule, in the markets, some 9H ceramic coating with very cheap prices to attract people, if they are really 100% real nano liquid? Absolutely no, they are stretching the truth to consumers.