Darco D-530 80/20 bronze acoustic string set 13-56. The Darco line of acoustic strings promises quality, sound and value in every pack. They are designed for the pros and priced for the working musician so every guitar player can afford to change their strings as often as needed to keep their guitar sounding new all the time. Darco acoustic strings are meticulously constructed using a tin-plated steel core wire and high quality wrap wire. Darco offers guitar players that pre gig peace of mind or heading to the studio fresh set string change.