... ,OHSAS18001 Mintolerance+/-0.2mm quartz window plate, quartz plate, quartz disc Company: Donghai Shengda Quartz Products Co., LtdCertification: ISO 9001, ISO14001 ... : thin quartz plate,clear quartz plate, quartz disc, square quartz plate, circular quartz plate, custom quartz plate, quartz glass sheet,quartz glass ...