Ernie Ball Cobalt guitar strings last longer, retaining their brightness long after other strings have given up the ghost. Steve Morse reported having a set on one of his guitars "for several weeks," and with daily use - "sweaty hands" and all - the Cobalts "still sound bright... They just don't have that dead sound," he says. So, with higher output, better sound, and the monetary benefits of not having to change strings so often, Cobalts have it all over traditional alloy formulations. Check out a set of Ernie Ball Cobalt strings Punchier, higher output stringsBeefier lows, with increased definition and growlIncreased midrange focus, harmonics, and sustainLonger-lasting than conventional strings.010, .013, .017, .026, .036, .046Made in USA