bout this item Long-Lasting Balance and Warmth: XS Phosphor Bronze strings have the longest life of any D Addario acoustic string, with no fraying, peeling, or tonal dampening thanks to the ultra-thin XS film coating Strength and Stability: With a NY Steel core and Fusion Twist technology, XS Phosphor Bronze offers greater break strength and unmatched tuning stability staying in tune 131 percent better than standard acoustic strings Strings for Every Style: From jazz to metal to rock, bluegrass, blues, folk and more, we make great sounding strings for every genre and level from beginner to pro, including strings for bass, acoustic, classical, and 12-string Sound Better, Play Better: Shop our whole collection of guitar accessories including string winders, picks, straps, capos, tuners, cables, gear bags and cases, plus strings for banjo, mandolin, ukelele and more Made in the USA: As the world s largest and most respected maker of musical accessories, D Addario guitar strings are made to exacting specifications at our cutting edge New York production facility