D'Addario Electroplated Steel strings are made using a new electroplating technology that incorporates digital controls to maintain uniform plating thickness and finish. Conventional plain steel guitar strings utilise a tinned, high tensile steel alloy; the wire is passed through a hot molten tin bath and then mechanically wiped to remove excess tin and possible defects. With this process, the tin coating thickness can vary and the heat can affect the temper of the steel wire.
Electroplating steel wire is far more exact in controlling the plating thickness, and introduces much less heat during the process. The result is a smoother feeling, more consistent plain steel string.