JBL Arena 8IW 8" Premium In-Wall Loudspeaker - Each Sound Inspired by JBL's legendary M2 Master Reference Monitor Paintable, nearly invisible zero-bezel magnetic grill Superior XL-2 installation bracket General Specifications Mounting Depth3-13/16" (97mm) Compatible Wall Material Thickness0.5"  2.0" (130mm  250mm) Shipping Units of MeasureEach Warranty5 Years Pre-Construction Bracket Part numberPCK8 Back Box Part Number FBB8 Audio Specifications Impedance8 ohms Recommended Amplifier Power100W Frequency Response30Hz - 20kHz Loudspeaker Sensitivity:88dB 2.83V @ 1mYes Low Frequency Driver Size and Material8" (203mm) Polycellulose Woofer High Frequency Driver Size and Material1" (25mm) Silk-Dome Tweeter