Check the listing for details. Celestion CDX1-1746 - Compression Driver / Ferrite - 1" - Screw-On. Condition: New. Listed at 72.99 USD. Celestion CDX1-1746 - Compression Driver / Ferrite - 1" - Screw-On Product Features 1" exit, ferrite magnet compression driver with 1.75" edgewound copper clad aluminium voice coil 40 Watts RMS power handling (AES standard)110 dB sensitivity Sound Castle™ clamping ensures even pressure on diaphragm assembly for reduced distortion One piece PETP diaphragm and surround Finite Element Analysis (FEA) used to optimise both magnet assembly and acoustic design General Specifications Power rating - 40WrmsNominal impedance- 8ΩFrequency range- 1200-20,000HzSensitivity2- 110dBRecommended min. crossover (12dB/oct)- 2200HzVoice coil diameter- 44mm/1.75inVoice coil material- Edgewound copper clad aluminiumMagnet type- FerriteDiaphragm material- PETP filmSurround material- PETP filmMounting InformationOverall width- 120mm/4.7inOverall depth- 56mm/2.2inFitting- Screw (35mm, 1.38in dia)Throat exit- 25.4mm/1inUnit weight- 2.3kg/5.1lb