The Polk Audio PB LC80i Pre-Construction Bracket works with vanishing series 80F/X-LS, 80F/X-RT speakers. It attaches to your studs or joists before drywall is hung. It designates the exact location and exact cut space, where your loudspeaker will be installed. It gives your electrician a wiring target and give your drywaller a hole template.
The pre-construction bracket adds that extra pinch of energy-harnessing, super-efficient rigidity that a Built-In Speaker needs, one more step toward keeping your built-in loudspeakers vibration-free, with added efficiency and less audio "print through."
It is the inexpensive alternative to custom performance enclosures and gives you more flexibility for speaker placement.