DR Strings NRB5-45 Hi-Def Neon Red strings feature a specially-developed K3 coating that lights up under UV light and fends off oxidation and grime. The coating doesn't affect the sound at all, in fact, it keeps the strings sounding fresh for longer. Like all strings by DR, these Hi-Def Neon strings are made by hand in the USA. This particular pack has been compiled for 5-string electric basses.