Ernie Ball 2923 M-Steel Super Slinky 9-42 Electric Guitar Strings. The Ernie Ball 2923 M-Steel Super Slinky 9-42 are a set of electric guitar strings made with a “Maraging” steel alloy and with a super slinky scale .009 .011 .016 .024w .032w .042w. M-Steels produce a rich, full tone and offer greater output, greater stability and greater durability
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