Marine Stereo Waterproof Boat Radio Mp4 Player Digital Media Bluetooth Receiver. Bluetooth Audio Wireless Steaming. 4 x 45W output. Frequency Range (Hz):20Hz-20000kHz. Power supply:DC 12V. Cutting Size of Reference. Dimensions Mounting Hole:88.12mm. Dimensions Mounting Depth:70mm. What’s in the package. 1 x Head unit. 1 x Mounting bracket. 2 x Mounting screws. 2 x Mounting nuts. 1 x USB cable. 1 x Power Cable. 1 x User’s manual. All items will be tested in advance before sending out. Gushi, our company is dedicating to reseach & development of marine audio series products. If you are dissatisfied for any reason, please donot be quick to leave negative/neutral feedback. Our working time:Monday to Friday.