If you want an actual firemans jacket they have them on amazon https://www.amazon.com/Viking-Professional-Journeyman-Waterproof-Resistant/dp/B00H88KNUY/ref=sr_1_8?crid=1MT0L5BD9CJ48&keywords=fireman%2Bjacket%2Badult&qid=1652374342&sprefix=firemans%2Bja%2Caps%2C121&sr=8-8&th=1&psc=1#:~:text=the%20VIKING%20Store-,Viking%20Professional%20Journeyman%20300D%20Rip%2DStop%20Fire%20Retardant%20Reflective%20Jacket%20%2D%20Fire%20Resistant%20Hi%20Vis%20Jackets%20for%20Men,-4.6%20out%20of
I got it from this website: https://next-episode.net/chicago-fire/season-10
Idk how truthful this site is, but it makes sense. It had the finale air date either late last night or early this morning.