The fireproof door lock is required to open the door quickly and conveniently, so there is no lock cylinder.

https://ztfiredoor.com/15730.html

flush fire rated door,fire rated swing doors,120 min fire rated door,2 hour fire rated door price,1 hour fire rated door with vision panel,commercial fire rated doors,flush fire rated door,fire rated folding doors,120 min fire rated door,1 hour fire rated door with vision panel,residential fire rated doors,flush fire rated door,30 in fire rated door,120 min fire rated door,1.5 hr fire rated door,1 hour fire rated door with vision panel