GHS DY33 Spare 4-D String for Guitar Boomer Low-Tuned String

Replace the D string in your set of GHS Guitar Boomers Low-Tuned Strings with the DY33. This string is meant to sit in the 4-D position of your guitar, but practically speaking, it's not a D string per se: GHS Guitar Boomers are meant to give you a hefty, powerful tone in multiple low tunings.