DR Strings DDT-11/54: These strings stay in tune! Deliver notes at lower pitch with clean and clear sound. Change tunings easily, drop with confidence & accuracy. DDT strings maintain their intonation at lower tunings and sound right, thanks to the hex core construction. Specifications Tension: Extra Heavy Gauges: 11, 15, 19, 32w, 42w, 54w Material: Nickel Plated Steel Core: Hexagonal Series: Drop-Down Tuning