The Von Frankenstein Monster Gear Jeff Loomis Sentient-6 Signature Set guitar strings are made on a U.S. workbench using the best-available, domestically sourced, raw materials. Each string in the Jeff Loomis Sentient 6 Signature set is made by hand, one at a time, with nickel-plated steel that’s carefully wrapped around a treated hex steel core. Through this meticulous process, Von Frankenstein ensures the quality, feel, and durability required by the most discerning of tone aficionados.