If you're looking for a great sounding set of guitar strings, look no further than these Coated Medium Guitar Strings from Monoprice!These strings are made of coated steel, for the E and B strings, while the larger strings are composed of an hexagonal core wrapped with coated nickel alloy wire. They include a rust-resistant coating and gold plated ball ends.Specifications:E - 1st Coated Steel .011 (0.28mm)B - 2nd Coated Steel .014 (0.36mm)G - 3rd Nickel Alloy Wound .021 (0.53mm)D - 4th Nickel Alloy Wound .028 (0.71mm)A - 5th Nickel Alloy Wound .038 (0.97mm)E - 6th Nickel Alloy Wound .049 (1.24mm)*** 30-day easy returns. No restocking fee. Free lifetime technical support. 1 year warranty. ***