STUDIO 6 66 LCR Cinematic Sound Dual 6.5" 2-way In-Wall Loudspeaker, 1" (25mm) Compression Driver with High-Definition Imaging (HDI™) waveguide, Dual 6.5" (165mm) Polyplas® woofer, Nominal Impedance 6-Ohm, Sensitivity 91dB,Power Handling 50W RMS (200W Dynamic), Recommended Amplifier Power 25W - 150W, Frequency Response 45Hz - 20kHz, Crossover Frequency 2.5kHz, Grille Dimensions (HxW) 8.2" x 18.6" (209mm x 473mm), Cutout Dimensions (HxW) 7.1" x 17.4" (180mm x 443mm),Mounting Depth 3.74in (95mm)