EXL145 is a popular choice for rock and metal where heavier gauges are required. A plain 3rd/G string offers more flexibility than traditional 12-gauge electric strings. Optimized for down tuning! XL Nickel Wound, D'Addario's most popular electric guitar strings, are precision wound with nickel plated 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. String Gauges: Plain Steel 0.012, 0.016, 0.020 Nickel Wound: 0.032, 0.042, 0.054.