The Skar Audio SDR-10 D4 10" dual 4-ohm subwoofer was engineered to dish out reliable, hard hitting, and low spectrum sound. Featuring a high flux ferrite motor, this woofer will provide extreme power handling for extended periods of time. The SDR series will quickly become a customer favorite, as it's perfect for people just entering the world of car audio all the way up to seasoned pros. The SDR-10 dual 4-ohm 10-inch car subwoofer features a 2.5” high temperature 4-layer high temperature copper voice coil that is attached to our Skar Audio signature red spider. The surround on the SDR series is a high roll foam surround which allows the woofer to produce riveting low end bass response. The SDR series has a max power rating of 1,200 watts and a RMS power rating of 600 watts. Sensitivity (Spl): 82.5 dB, Xmax: 13.5mm one-way, Fs: 39 Hz, Frequency Response: 28 Hz- 300 Hz, Mounting Depth: 6.08". 10-Inch Dual 4-ohm Car Subwoofer Peak Power: 1,200 Watts | RMS Power: 600 watts 2.5" 4-Layer High Temperature Copper voice Coil High Roll Foam Surround and Competition Grade Pressed Paper Cone Frequency Response Range: 28 Hz - 300 Hz | Sensitivity: 82.5 dB