With the creation of our new EXP Wire manufacturing facility we have invested in wire coating machinery which allows us to fully control and develop advancements in coating technology for wound strings that is second- to-none in the guitar string industry. Of equal importance is our exclusive compound-plating process for plain steel strings. This is a monumental improvement in extending the life of plain strings, while preserving the integrity of the string's feel and tone.

The EXP Wire machine draws wire from rod, anneals, cleans, coats, cures and spools wire in one continuous process. This ensures our tight tolerances and specifications are adhered to.

We test every spool of wire with a sophisticated digital micrometer which measures the concentricity of the coating thickness to 2/10,000 of an inch. We have successfully reduced the coating thickness by at least 50%, which allows the string to retain even more of its inherent brightness and natural uncoated tone, while maintaining EXP's renowned durability and long-life characteristics. You won't believe they are coated!

Traditional plain steel strings are made of high-carbon steel which is plated in a layer of tin to prevent them from rusting. Tin is a proven, excellent corrosion inhibitor for strings, however traditional application methods often leave pin holes, thin spots and areas of poor adhesion, which allows moisture and the elements to seep in and create corrosion. This is why you get dark spots on your plain strings, which quickly spread and create a gritty, rusty feel and appearance.

Our new (exclusive to D'Addario) compound-plated process allows us to put up to 4X as much tin on the string, eliminating thin or exposed areas on the string. These plain steel strings feel and sound exactly the same, but won't corrode, giving the strings at least 4X more playing life.