The Fortis CCTV Colour Wireless cameras and receivers use 2.4Ghz Locked Frequency for exceptional wireless quality. Four channels available. Outputs both Audio and Video signals. Cameras supplied with 12V Power Adapter. Also ideal for retail, office and factory environments. Receivers connect to TV or DVR (RCA connection). Connecting receivers to a PC monitor requires VGA converter. Fortis products are highly reliable, quality tested and have a one year warranty.Frequencies:CH1: 2.414GHzCH2: 2.432GHzCH3: 2.450GHzCH4: 2.468GHz