The QED XT25 Speaker Cable w/Fisual Surefix Spade Plugs uses X-Tube technology. This first came to prominence in 2005 with the launch of the world renowned Silver Anniversary XT the most highly awarded mid-range cable in the world winning the What Hi-Fi Product of the Year three years in a row. These design principles also grace the multiple award winning XT40 speaker cable and XT25. As frequency increases electrons flow more and more towards the periphery of a conductor so that if the frequency is high enough only a very thin layer (or skin) on the outside of the conductor is used. This \"skin depth\" varies for different materials at a fixed frequency and in copper it means that if a conductor has larger than 0.66 mm2 cross-sectional area not all of that area is available for an analogue music signal to use. The cable comes fitted with Fisual Surefix spade plugs ensuring optimal signal integrity. Please Note: This cable comes pre-built images are for reference only.