Gauges 9-11-16-24w-32-42. Nickels are the most popular of the Ernie Ball Slinky guitar strings. They’re made from nickel-plated steel wire wrapped around tin-plated hex-shaped steel core wire. The replacement strings produce a well-balanced all-around good sound. Ernie Ball strings are precision manufactured to the highest standards and most exacting specs to assure consistency, optimum performance, and long life. Ernie Ball is the pioneer of rock and roll guitar strings. Jimmy Page, Eric Clapton, Steve Vai, and Slash are among the long list of Slinky players.