CMS Micro Speakers CUI Devices CMS Micro Speakers are compact, low-profile speakers housed in rectangular frame packages as small as 15mm x 11mm up to 18mm x 13mm. The CMS series, with profile depths as low as 2.5mm, offers input power ratings of 0.7W or 0.8W and impedance of 6Ω or 8Ω. These rectangular micro speakers feature Mylar cone types, neodymium (NdFeB) magnets, and a number of mounting styles, including wire leads, solder pads, and spring terminals. Sound pressure levels range from 88db up to 93dB at 0.1 metres, making the CMS series ideal for space-constrained consumer electronics, portable equipment, and more.