This Neet HD product allows you to extend your HDMI cable range up to 100 metres (at 1080i) by using Ethernet Cat5e or Cat6 network cables (Note: Good quality and preferably shielded cables are recommended for reliable performance). This type of cable (most common to computer networking) is relatively cheap to buy and is also readily available. It is relatively thin, flexible and easy to feed throughout any installation network and can also be easily self terminated so lengths can be tailored to meet the exact requirements of any home or commercial HD installation. The source HDMI cable plugs into the transmitter unit HDMI input... then 2 x Cat-5e / Cat-6 cables are used to send the HD signal to the receiver unit in lengths up to 100m for 480p or 1080i (eg Sky HD) or 60m for Full HD 1080p... then another HDMI cable is used from the receiver unit to the HDMI input of the HDTV, monitor or projector display device... simple. Note: In order to achieve reliable transmission and pure HD picture quality we highly recommend using SHIELDED CAT-5e or CAT-6 cable. As with most AV cables, lower quality cables may not achieve reliable performance over the long distance ... Of course, we also strongly recommend using high quality HDMI cables no matter what length you are running at each end... Neet advanced High Speed HDMI (v1.4) cables are available from our Amazon store front and come with our specialist customer service and *** LIFETIME WARRANTY ***