The PSU-300CVC is a sound system upgrade for 2016-2020 4-door Honda Civic models without the optional factory Premium amplified sound system and are not touring models. This 300-watt upgrade boosts the overall sound performance of the factory sound system. The PSU-300CVC consists of an 8-inch powered subwoofer, Compact 4-Channel amplifier, and a remote bass knob. The system is compatible with 2016-2020 Honda Civic 4-door models that do not have the optional factory Premium amplified sound system and are not touring models. All the components are hidden away, so no valuable Trunk storage space is used. The subwoofer is just 3-inches Deep at its tallest point, so it and the amplifier fit neatly under the front passenger’s seat. Aside from maintaining storage space and utilizing a hidden installation, placing the subwoofer close to the front of the car allows for a proper sound stage in front of you, ensuring the best bass and imaging experience. The PSU-300CVC is designed for plug-and-play installation, which reduces labor time and gets you on the road quicker. The subwoofer and amplifier are pre-assembled onto the civic-specific bracket, so there’s no guessing where the products should be installed and no time spent connecting them to the bracket. A civic-specific wiring harness is included, so no extra parts are needed. The bass knob mounts onto the dashboard so you can make bass level adjustments from the driver’s seat. The PSU-300CVC is compatible with the factory Honda base radio, an Alpine Universal head unit, or other aftermarket radio. The PSU-300CVC is authorized to be Sold By and Shipped From Amazon. For professional installation, visit the store locator on the Alpine USA website to find an authorized Alpine retailer near you.