The Polk Audio PB LC65i pre-construction bracket attaches to your studs or joists before drywall is hung. It designates the exact location and exact cut space, where your loudspeaker will installed. It gives your electrician a wiring target and gives 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.