A model in Gucci’s Milan Fashion Week show staged an unplanned protest of the label’s “offensive” use of straitjackets on Sunday, claiming at least one other model was so “disgusted by the clothes” he walked off the job.

London-based model Ayesha Tan-Jones, who identifies as non-binary, said the Gucci designs were deeply offensive and they spontaneously decided to scrawl “Mental health is not fashion” on their hands before going on the runway.

“As an artist and model who has experienced my own struggles with mental health, as well as family members and loved ones who have been affected by depression, anxiety, bipolar and schizophrenia, it is hurtful and insensitive for a major fashion house such as Gucci to use this imagery as a concept for a fleeting fashion moment,” Tan-Jones, 26, wrote in an Instagram post.

Models rolled down the runway on a conveyor belt Sunday, dressed in straitjackets in a stark white room — reminiscent of a mental health treatment facility.

Responding to the furor on Instagram, Gucci claimed the “utilitarian clothes” by creative director Alessandro Michele were meant to be a statement on how fashion “prescribes social norms” and were never meant to be sold to the public.

But Tan-Jones said the stunt was “vulgar” and claimed many other models were equally upset about being forced to wear the designs — with at least one man walking off the job and going home, they said.

“It is in bad taste for Gucci to use the imagery of straight jackets and outfits alluding to mental patients while being rolled out on a conveyor belt as if a piece of factory meat,” Tan-Jones wrote.

“Many of the other Gucci models who were in the show felt just as strongly as I did about this depiction of straitjackets, and without their support I would not have had the courage to walk out and peacefully protest.”