Thank you for your cooperation! Notes: Not for trucks. Speaker unit size: 8. Size(L X W X H): 350mm x 245mm x 85mm / 13.78 ” x 9.65″ x 3.3. Sound type: full frequency (with treble) subwoofer. 8 Amplified Low Profile Subwoofer System offers a maximum power of 800 watts. It lets you pump out some great low frequency bass volume to enhance the party vibe making it a great addition to your car music audio system. The integrated amp in the compact subwoofer features low pass crossovers & a control for adjusting input sensitivity from 0.12V to 3.5V. Includes variable bass boost, control the subwoofer level w/ the remote level control module. With height of just 3.3, it’s a perfect solution when space is an issue, it can easily fit under the seat of most vehicles! Total dimension is 13.78 ” x 9.65″ x 3.3 & includes mounting hardware. A great addition to your car stereo sound system. High & Low Level Inputs. A low level (RCA) input is measured in voltages. A high level (+/- wire) input is measured in wattages. Both essentially carry signal from your receiver to your amplifier to your speakers. Variable Bass Boost allows you to adjust the low bass within the boost range to just the way you like it. The gain control is not for adjusting volume. It simply adjusts the amount of signal that is coming from your receiver and going to your amplifier. The external configuration of high strength stainless steel horn protection net cover. 8 inch 800W high power design, with the volume controller. Low frequency ability of the bass horn, high quality low tone output. Fine workmanship and good performance. Easy to install, can be installed directly under the driver’s seat. Durable in use. We provide clear pictures, measurements where possible. Please check as much as possible to make sure the item is the one that you need. Please allow 0.5-1 inch difference due to manual measurement. Although instruction is included. Professional Installation Is Highly Recommended! Installation instruciton not inclued. If you are satisfied with our item, could you kindly give us 5 stars feedback? We have always been doing our best to provide the best service and reliable products for every customer. We will reply your emails and questions within 24 hours. But, we’d like to assist you to receive the goods smoothly if there are anything we can do here. Items will be sent via Hermes, RoyalMail, & Yodel. We will check and offer a good solution to you. We are only responsible for once re-sending expense for replacement due to defects.