Power Acoustik NX-3 PRO Audio Tweeter - 200W MAX &ndash; Single, 109DB 1W/1 M Very Efficient (and Loud!) Horn Loaded Compression Tweeter 1.75" Aluminum Dome Diaphragm with Phase Inversion Plug 6dB Crossover Capacitor Included. Freq. Resp 3kHz - 20KHz 4-Ohm Impedance. Efficiency: 109dB with 1 watt at 1 meter 100 W RMS , Sold Individually