The CSS230 is a brilliantly innovative back-box design with an impressively shallow 50mm (2”) mounting depth, custom built to offer hi-fi levels of performance in spaces where no high quality speaker has gone before. The hybrid back-box provides the best of all worlds for installer and customer. Combined, the three proprietary 3" mid-bass units achieve the bass output of a 6 1/2" driver, all from a super-stealthy flush-fitted profile.