US Trademark Classification US09 Scientific and electronic apparatus 低频扬声器（009-671） Class 09 低频扬声器 009-671 Chinese 低频扬声器 English Woofers Spanish Woofers Term ID 009-671 Class 09 Type Goods Status Active · added, not since modified (A) Effective date 2001-06-01 Version 07-1997