The carbon steel customized by Huashu from steel mills is different from fake carbon steel with more iron (Fe) impurities on the market. The carbon content of the carbon steel customized by the new Huashu series drum is based on the carbon content of Luru’s original high-end carbon steel model. The content is customized as a reference, the ratio is very stable, and the feature is that there is no "iron knocking" and it solves the problems of rust and intonation.