EU Trademark Classification EU09 Scientific and electronic apparatus 双向触发二极管（DIAC）（20990） Class 09 双向触发二极管（DIAC） 20990 Chinese 双向触发二极管（DIAC） English Diacs Site ref. 20990 Class 09 Included in Harmonised Database (HDB), Nice Alphabetical List, WIPO Madrid Goods and Services (MGS)