The main feature of these types of system is that they are simple to install and unobtrusive. They follow the shape and contours of irregular fence lines and are not constrained to "line of sight" applications. This makes them ideal for irregular shaped sites. This means that they do, usually, require a specific physical barrier such as a wall or fence, although the Taut Wire systems can form their own physical barrier It is essential that they work on many different types of structure such as chain link, welded mesh and palisade fencing. The Taut Wire systems must also have a free-standing capability