The easy pre-linked installation process means there is no need for wiring into a mains supply or the services of a qualified electrician. There is no need to damage your home décor lift carpets or run cables. All the components are self contained & no connections are required between the units. Extra door/window contacts PIRs & smoke detectors can be added to the systems. You can also programme keyfob remote controls & keypads for added control convenience. Batteries in the devices will operate for a minimum of two years before they need changing. Regular testing & battery changes (when notified by the systems) will ensure reliability & peace of mind.