The B&W CCM 818 includes additional features such as a unique blue interior body color for the cone/bass driver, a frequency response rate of 45Hz-22KHz, a nominal impedance rating of 8 ohms, an 11" total body diameter, an included pre-mount kit specifically designed for this model speaker (PMK-C8), and a semi-white matte plastic edge encasing which can be painted to a custom matching ceiling or wall color.
The B&W CCM 818 speaker unit was designed to mimic the specifications and body format of the similar B&W CCM 817 speaker. The 818 offers a larger driver unit (8") but includes the same basic specifications and delivers what B&W claims to be the same quality sound as the CCM 817.
Note: The quoted MSRP is for a single speaker unit; a pair sells for double the MSRP of one speaker.