A 4-channel Bluetooth amplifier is a versatile audio device that offers multiple ways to play your favorite music. With four channels, it provides a powerful output that can connect to multiple speakers, for a full surround sound experience. It also features Bluetooth connectivity, allowing you to wirelessly stream music from your phone, tablet, or other Bluetooth-enabled devices. Additionally, You can also insert an SD card into the amplifier to stored on the card. Additionally, the FM radio function allows you to tune in to your favorite radio stations and listen to them through the amplifier. The USB function lets you connect a USB device to stored on it. Finally, this amplifier offers additional functions that enhance your listening experience, such as volume control, and bass and treble adjustment. Overall, this 4-channel Bluetooth amplifier with TF card, FM radio, USB, and function is a comprehensive audio solution that provides multiple for enjoying your favorite music. Product Name:4 Channels Amplifier Model Number:BT-998 Rated voltage:DC12V (If you want to use it , please purchase the power adapter yourself) Ratedpower:60w x 4 power:400w x 4 : equal 95dB Frequency Range:20Hz-20khz Impedance:4-16ohm Distortion rate:0.4% support:U Disk/FM Radio/SD Card/Remote control Type:Car Amplifier (If you want to use it , please purchase the power adapter yourself) Colour:Black Material:Aluminum Plastic Size:170x100x45mm Package Contents: 1 * Audio Amplifier 1 * remote control Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.