The Tri-Pro has been fire tested for over 4 hours
  within a wall, with the installation plate as primary
  method of installation.

  The plate has been the subject of extensive
  research to ensure that it allows the Tri-Pro to
  operate successfully as a Fire/Smoke/Volume
  Control Damper in ambient and elevated
  temperature conditions.

  The design allows the installer to fix the Tri-Pro into
  the structure quickly and professionally with
  minimal equipment required.

  As shown, the installation plate has a number of
  diagonal slots pre-punched to assist the installer.