Access Door - The PFN access door is not insulated and can only be used on fire rated walls. It comes with a 1” flange for an easy flush installation on any type of surface material. As per UL standards, once the installation is complete and the provided springs installed, this door will be self closing and self locking. It should not be used in situations where protection against temperature elevation is required. The largest fire rated PFN door available is: (36’’ x 36’’)