HI-DEF NEON? Color Coated Acoustic Guitar Strings are available in a wide variety of luminescent color options designed to give your stage presence a little extra pop, especially under UV black lighting. They feature a hexagonal core wire and a silver plated phosphor bronze wrap wire on the wound strings. All strings include the neon colored K3? coating, delivering longevity, more projection, fewer unwanted overtones, plus enhanced clarity and articulation. K3? Coated applied to the wrap wire is extra hard to maintain string brightness while extending life The coating eliminates unwanted overtones, helping projection, clarity and articulation Dayglow coating is luminescent under black lights or uv lights