EU Trademark Classification EU01 Chemicals Drilling muds (Chemical additives to -) Class 01 Drilling muds (Chemical additives to -) 2691 钻井泥浆用化学添加剂 Chinese 钻井泥浆用化学添加剂 English Drilling muds (Chemical additives to -) Site ref. 2691 Class 01 Included in Harmonised Database (HDB)