The COMP-4CLS is a 1" Exit Compression Driver that features a titanium diaphragm and is mounted with screws. The voice coil diameter is 1.75". This compression driver is built to engineering perfection using the most innovative design concepts and materials. B-52 transducers are manufactured to maximum tolerances by some of the most well-respected engineers in the world. All loudspeakers are subjected to a wide array of quality-assurance tests during and post assembly. It's for these reasons that B-52 speakers typically have a 0.2% return rate and are backed by a five-year warranty.