Allows Up To 4 Camera Video and Audio Inputs. Then just plug the Video/Audio output cables from the Sequencer into your TV or VCR input jacks. A very economical device that enables auto switching between multiple cameras. Elapse time is adjustable from 1 to 60 seconds. Or if you want to view any one camera for a longer time simply press the corresponding button 1 thru 4. Operates on 120 volts AC.