The Lanzar OPTIUTV10B Opti-Drive Bluetooth Waterproof Speaker and Amplifier System gives your vehicle versatile sound power on the go. The system includes a total of four 4'' -inch marine grade construction speakers, that'll help you cruise around with additional sound power and style. This Opti-Drive Combo Amplifier and Speaker system includes sleek, bullet-design style speakers, 4-channel marine power amplifier, Bluetooth connection console and all the necessary cables and wiring -- to provide mobile audio on the move. Enjoy instantly streaming and high-powered Bluetooth wireless music streaming with versatile sound power! It works with all of your favorite devices and system setup is easy. Now you can enjoy mobile music on the go with the Lanzar Opti-Drive Bluetooth Waterproof Speaker and Amplifier System.