Without wishing to preach to everyone and keep making the comment about how important mains cables can be, it really does go without saying that your mains power cords play a massive part in how your system reproduces sound. It is equally important to partner your mains cable to the connection points at either end. The power from your mains supply immediate point of contact is the mains connector, this has to be right and voltage needs to flow through with minimal restrictions.
Mains power cord designs are huge in numbers, every conceivable material, pattern and type can be found in todays market, the principles are the same, good clean, unrestricted, mains supply. Choose the right connector that suits your project, from the humble and infamous silver plated 13A MK plug, Martin Kaiser or Wattgate and the outstanding quality from Furutech and Oyaide.