Speco's  6" aluminum PA horn is weatherproof. It offers a frequency response of 250 to 15,000 Hz with a 10 watt RMS/15 watt maximum power rating. It features a 105 dB sensitivity and a 4 ohm impedance. Alternatively, it is available with an 8 ohm impedance under model number SPC-10. Technical Specifications Dimensions 6" (Dia) x 6" (L) Frequency Response 250-15,000 Hz Impedance 4 Ohm Material Aluminum Max Power 15 Watts Mounting Bracket Included RMS Power 10 Watts Sensitivity 105 dB