Jim Dunlop Dunlop Heavy Core Electric Guitar Strings - Heaviest Gauge : Heavy Core Strings are uniquely designed for the player that enjoys higher tension at standard tuning or normal tension at dropped tunings. The proprietary core-to-wrap ratios are meticulously calculated so the player can really "dig in" while retaining sound fundamentals. Heavy Core Strings, like all Dunlop Strings are manufactured with the highest quality of materials and engineered for great tone, balance, and feel.  "Heaviest" Gauges: 12-16-20-32-42-54