Ernie Ball 12-String Nickel Slinkys

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, resulting in a bright and well-balanced tone 
Signature Slinky feel 
Precision manufactured to the highest standards and most exacting specifications to ensure consistency, optimum performance, and long life 

Element Shield Packaging prolongs string life and keeps strings as fresh as the day they were made 
Made in California, USA with the finest and freshest materials