Conair makes products to help people look like their best selves ... but, one model claims it did the exact opposite to her -- suing the company after she says their products left her head bloody and mangled.

Lea Encarnacion -- a former New York City hair model -- is suing the conglomerate for an alleged 2020 incident where she says she worked as a hair model for the brand at a convention in Long Beach.

Encarnacion says stylists at the event employed by Conair "negligently applied" a hair-bleaching product to her locks and didn't remove it in a timely manner.

Lea says she was left with a severely injured scalp -- and, she's included pictures she says show the extent of her injuries.

Word of warning ... these pics ain’t for the faint of heart -- 'cause they show her bloody, scabbed-up scalp. The scabbing adds a yellowish tinge to the blood-red injury, and obviously the hair’s completely gone.

According to Lea's attorneys, the hair hasn't grown back -- and, she now has a heart-shaped bald spot on top of her head.

Lea's suing for general negligence and products liability, and the case is set to begin trial this month. We've reached out to Conair about the suit ... so far, no word back.