While optimally designed for today's modern, shorter scale electric baritone guitars, EXL158's are also an excellent solution for deep, down-tuning on most standard electric guitars. XL Nickel Wound, D'Addario's most popular electric guitar strings, are precision wound with nickelplated steel onto a carefully drawn, hexagonally shaped, high carbon steel core. The result, strings with long lasting, distinctive bright tone and excellent intonation, is ideal for the widest variety of guitars and musical styles.