Voice Coil: 2 Black Aluminum 4-Layer. Frequency Response: 50Hz - 4.5KHz. Ported: 0.5 - 1.0 cu. Our company has been in the stereo business for over 10 years.We will gladly answer any technical questions you have. The item "2 DS18 SLC-8S 8 Inch Car Subwoofers 800 Watts 4 Ohm Subs Select Series Pair NEW" is in sale since Tuesday, January 28, 2020. This item is in the category "Consumer Electronics\Vehicle Electronics & GPS\Car Audio\Car Subwoofers". The seller is "stereo-needs" and is located in La Mesa, California. This item can be shipped to United States.