This kit includes a pair of BLAM 8 Inch Under Seat Subwoofers and a pair of sub woofer adapter cables. BMWs are very challenging to equip with new audio upgrades since they have very shallow subwoofers under the front seats. The BM 200 WN hi-performance BMW-dedicated 200mm (8 inch) extra-flat underseat subwoofers from BLAM are custom made to make the installation process faster and make the sound image more precise and clear. The BM200WN woofer has been designed specifically to mount in the original location. It replaces very advantageously the 165 mm woofers installed as standard in many models. Compatible with the BMW Series 1/3/5/6/7 and X1/3/5/6. Max power 120 W. Frequency response 40 Hz to 1 kHz. Lightweight and rigid fiberglass membrane. Spider long life Conex. 35 mm coil on aluminum support. High-powered neodymium motor 34.5 x 7 mm. Max power: 120 W. Nominal power: 60 W. Response: 40 Hz – 1 kHz. Sensitivity (2,83V/1m): 91 dB. Magnet size Ø x h: 34.5 x 7 mm 1.358”x 0.276′. Total driver displacement: 0.6 l 0.021 cf. Weight of one component: 0.52 kg 1.146 lb. Voice coil Ø: 35 mm 1.378. Voice coil height: 10 mm 0.394. Effective Ø (d) 167 mm. Sd 219.04 cm². Re 2.0? Fs 51.71 Hz. Vas 17.75 L. Mms 35.96 g. Cms 0.263413 m/N. BL 4.31 Tm. Sensitivity (dB/ W / m) 85 dB. BMW sub-woofer adapter cable allows you to change the woofers underneath BMW front seats. Connects to original harness. Car models: The years stated refer to the model’s years of manufacture, please check the item description for information about any changes there may be within these productions years. BMW – 1 Series (F20/F21) (2011 – 2019). BMW – 3 Series (F30/F31/F34) (2012 – 2019). BMW – 5 series GT (F07) (2010 – 2016). BMW – Z4 (E89) (2009 – 2016).