The CT Sounds BIO-4-COX 4” 2-way coaxial car speakers are the perfect upgrade for your factory car speakers and are extremely versatile with the ability to be powered by your factory head unit, an aftermarket head unit, or a multichannel amplifier. The speakers are sold as a pair and include (2) 4” signature CT Sounds speaker grilles, (2) premium speaker wires with pre-crimped female spade connectors, (8) 1” mounting screws, (8) mounting clips, and (1) product manual with wiring diagrams for easy installation. 

The name “BIO” derives from the Biosphere, Earth’s lowest atmospheric layer. And just like the name suggests, these 4-inch speakers come closer to earth delivering a nicely balanced tonal range at a price that won’t send you into space. The silk-dome tweeter combined with the polypropylene woofer delivers sound that is rich and full with tight bass and mids. Don’t just hear sound. Travel to the future and experience it.