OPTIMUS 6 1/2" Flush Mount Speaker System (120-1735) Specifications Faxback Doc. # 17096 Speaker Size:.........................................6 1/2-inch Full-Range Barium Magnet Weight:..............................................9.97 Oz. Power Handling:.........................................20 Watts Each (RMS) Maximum Power:................................................40 Watts each Impedance:...........................................................4 Ohms Frequency Response:..........................................80 Hz - 18 kHz Sensitivity:..........................................................91 dB Weight:..............................................1 LBs, 6 Oz. (620 gms) Dimensions:.........................3 5/32 x 6 13/16 x 6 13/16 inches (HWD) (80 x 173 x 173 mm) Specifications are typical; individual units might vary. Specifications are subject to change and improvement without notice.