US Trademark Classification US21 Household and kitchen utensils 双层蒸锅（021-594） Class 21 双层蒸锅 021-594 Chinese 双层蒸锅 English Double boilers Spanish Baños dobles Term ID 021-594 Class 21 Type Goods Status Active · added, not since modified (A) Effective date 2001-06-01 Version 07-1997