As our premium uncoated electric string, NYXLs offer higher break strength, enhanced tuning stability, and accentuated mid-range frequency response versus our standard strings, providing more presence and crunch to cut through the mix. Made with a NY Steel core, premium nickel-plated steel wrap wire, and Fusion Twist technology, NYXL electric guitar strings are tough enough and versatile enough to handle anything. This 11-56 Medium Top/Extra Heavy Bottom set is designed to maintain a comfortable playing tension when tuning down a whole step to D.