Martin MTCN160 2 Pack Titanium Core strings deliver the ultimate player’s experience with patented technology only available from Martin. Experience a new level of comfort and response with industry leading stability and superior corrosion resistance. Titanium is more flexible than steel, providing a very comfortable playing experience while remaining strong and durable. Martin uses pure Nickel to wrap the Titanium strings. Pure Nickel is naturally corrosion resistant and holds its tone for a very long time. The pure Nickel and Titanium work together to provide the ultimate corrosion-free string.