4 Zone Stereo Speaker Selector Switch With Impedance Protection by AVX Audio Four zone speaker selector turns on one or all four zones. Connect one pair of speakers or up to all four pairs without damaging your amplifier. Great for multi source control fo the sound in your house and or dwelling . Impedance protection prevents amplifier from damaging low impedance loads. You can connect up to four pairs of speakers to this speaker selector without damaging the amp due to impedance protection circuit . Accepts all standard types of speaker wire up to 14 gauge. Spring loaded terminals hold the bare wire tightly in place to prevent loose connections for years to come. Can be used in conjuction with AVX brand volume controls. If using impedance protection on the speaker selector then you would not use it on the volume controls . This speaker selector by AVX can handle high power | 150watts RMS/channel. 75watts RMS/channel with impedance protection at 8 ohms