WARNING – Qinhuangdao Silide Ceramic Technology advertises FDA compliant zirconia discs on Alibaba.com under the brand name KingCH. There is no publicly available FDA registration of the KingCH name, however there is a 510(k) registered under Qinhuangdao Silide Ceramic Technology for general zirconia blocks. We are unable to verify is this is the same block as the KingCH.