Ernie Ball 2215 Skinny Top/Heavy Bottom Slinky Electric Guitar Strings are the perfect hybrid set for those who like thick bottom strings without sacrificing the ability to solo on smaller strings. The wound strings are made from nickel-plated, steel wire wrapped around a hex-shaped steel core wire. The plain strings are made of specially tempered, tin-plated, high-carbon steel, producing a well-balanced tone for your guitar. All Ernie Ball strings are precision manufactured to the highest standards and the most exacting specs to assure consistency, optimum performance, and long life. Ernie Ball is a pioneer of rock and roll guitar strings. Jimmy Page, Eric Clapton, Steve Vai, and Slash are among the long list of Slinky players.