Hole Size Required - 8" Diameter. The woofer on the speaker is 6.5". The housing of the speaker is 9.5" Round. An 8" hole is required to mount the speaker. One stereo 2 channel speaker 2-way x 2 in-ceiling with a 6.5" mica polypropylene cone woofer with rubber edge and a 16.5 oz magnet delivers clear, distortion-free sound. The 2 x 20mm silk dome tweeter produces silky-smooth sound and works great in rooms where only one speaker can be installed.
Frequency Response: 69 Hz - 20, 000 Hz, Sensitivity: 88+/-2 dB, Impedance: 8 ohms, Crossover: 12dB per octave;
Power Handling Capacity: 40-Watts Nominal, 80-Watts Peak x 2. Solidly constructed, moisture-resistant speakers can be used in bathrooms, saunas, or under outdoor eaves. Not a 3-way speaker, Requires 2 channels (left & right wiring) from A/V receiver to be a single 2 channel stereo speaker