Small speakers, big sound. Boss All-Terrain Sound System speakers are only 2.5", yet they put out 400 watts of volume. 20 to 20,000Hz provides a full range of sound. 3.5mm auxiliary jack connects to your MP3 player. Mounts to handlebars with included brackets. Includes extra replacement grilles and remote volume control with weatherproof wiring. Suitable for 12-volt motorcycles, scooters and boats.