PYLE-PRO PDS445 1.75-Inch Titanium Ceramic Screw On Horn Driver At 8 Ohms Throat Diameter: 25.4mm(1 in) - Frequency Response: 1-20 kHz - Net Weight: 2.31 lbs. Mounting Screw: 1-3/8''-18TPI - Voice Coil Diameter: 44.4mm(1.75 in) Nominal Impedance: 8 OHM - Diaphragm Material: Titanium Rated Power: 300 W RMS, 600 W MAX - Magnet: Ceramic Sensitivity(1W/1M): 103dB/w/m - Outside Diameter: 4.72 in.