EXL120+, with its 9.5 gauge high E, is the ideal "step up" string set for players who are moving up from 9 to 10 gauge sets. Additionally, it's great for balancing tension between various scale length guitars. If you play 9s on a 25 1/2" scale guitar, try EXL120+ for your shorter scale length instruments to maintain more consistent feel and playability. 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.