The CCM664SR is a dual, two-way ceiling speaker featuring a 150mm (6in) glass fiber cone bass/midrange driver and two raised tweeters. The dual bass/midrange voice coil and sound heads allow for the combined use of stereo signals, facilitating the use of a single ceiling speaker in a unique installation area without the loss of a sound channel. The CCM664SR also includes a two-position stereo/mono switch, making the speaker highly suitable for use as a surround channel. With its integration of QuickDogs and plug-and-play functionality, installation is quick and easy.