Gauges 10-46, 52% iron/48% nickel, extremely durable and responsive. Resists tarnish, awesome resonance. 52% iron mixed with 48% nickel is the formula for Alloy-52, the material used in the Everly 9210 B-52 Rockers Alloy Medium Guitar Strings. This magnetically active alloy makes for an extremely durable, highly responsive electric guitar string, with awesome resonance characteristics. It resists tarnish up to 3 times over its nickel-plated steel predecessor and delivers more sustain and overtones. Alloy-52 is a mysterious metallic substance found in the desert just outside Pahrump, Nevada.