The steel doors are placed outside and the steel wooden doors are placed inside, which can improve the fire resistance time in case of fire.

https://ztfiredoor.com/20339.html

metal fire proof door for interior,30 minutes fire rated wood door,fire rated 90 minutes double door,fire exit door panic exit device,hollow metal interior fire rated door,fire rated steel door with window,metal fire proof door for interior,fire rate floor access door,fire rated 90 minutes double door,hollow metal interior fire rated door,emergency exit fire-rated security door,metal fire proof door for interior,core plate of fire door,fire rated 90 minutes double door,fire rated hotel door locks,hollow metal interior fire rated door