Pyle-Pro PDS182 1.5'' Titanium Screw On  Horn Driver 8 Ohm 1-3/8'' x 18 TPI Midrange/Tweeter Compression Horn Driver - Sensitivity:103db 1W/1M Titanium Diaphragm - 8 Ohm Impedance 1.5'' (44.4mm) Flat Aluminum Voice Coil - 120 Watts RMS/240 Watts Peak 13.5 oz Magnet Structure - Terminals 205 Type Frequency Response:1500Hz-20KHz - Fits Horns with 1 3/8'' x 18 TPI Threads