Pioneer TS-R1651D Coaxial Speaker (Black) Type - 3-way Coaxial/full range size - 6.25-inch, max power output - 300W, nominal power output - 40W RMS, frequency response - 30 Hz - 18 kHz, impedance - 4 ohm Sensitivity - 90dB Cone. Material - Multilayer mica matrix cone speaker grilles. Weight - 0.62 kg per speaker.