16 C.F.R. § 301.21 – Disclosure of used furs.

(a) When fur in any form has been worn or used by an ultimate consumer it shall be designated “used fur” as a part of the required information in invoicing and advertising.
(b) When fur products or fur mats and plates are composed in whole or in part of used fur, such fact shall be disclosed as a part of the required information in labeling, invoicing and advertising; as for example:
Leopard Used Fur or Dyed Muskrat Contains Used Fur