PowerBass OE-400 4" Mid-Range OEM replacements speaker for BOSE stereos. PowerBass noticed a lack of a good replacement option for one of the most troublesome speakers for installers and DIY'ers to effectively replace without removing entire enclosures or using oversized or mis matched impedance speakers. No highs no lows? Then look no further than the OE-400 BOSE ™ replacement speakers to wake up the audio in your late model vehicle or simply replace one that has worn from the test of time. To stand the test of time but also maintain the best possible sound they utilized a treated pressed paper cone, with a nylon accordion style surround. This keeps the sonic nuances similar for the application while utilizing a stronger motor structure and fine tuning the OE-400 also brings out more of the sound you have been missing from your late model OEM system Features - • 4" Mid-Range Speaker for BOSE™ replacement • OEM Drop in Replacement Design and Terminal Placement • Black Pressed Treated Paper Cone • Nylon Accordion Surround • 12 oz. Motor Structure • EFF Motor Structures (Efficient Flux Field) • 2-ohm System Impedance Specifications - • Nominal Impedance: 2-ohm • Material: Injection Molded PP cone with Carbon Fiber/ aluminum done tweeter • Magnet Size: 6 oz • Sensitivity (1W / 1M): 87 dB • Mounting Depth: 1.86 in • Size: 4 in • Sensitivity: 87 dB • Frequency Response: 80 Hz - 21 kHz • Power Handling (RMS/Peak): 40 / 80 watts