While some formerly anti-sheep farming groups are changing their views because of wool's biodegradable qualities, those at PETA are staying the course.
Australian model Stefania Ferrario has been enlisted by the extreme animal rights group to front another campaign against wool in New York.
The eight metre tall billboard in the city's Garment District attempts to convince shoppers to cross wool off their shopping lists.
The new PETA ad urges consumers to "leave wool behind".
Ferrario has more than 1.1 million followers on Instagram and, according to PETA, recently told her management agency, Bella Management, to add a clause to her contract stating that she won't wear any animal-derived materials in advertisements.
"I used to only think of fur as being bad in fashion, but once you learn the truth you have a moral duty to do better," she said.
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