Martin MFX130 Flexible Core Silk & Phosphor FX Custom, Full Set

Custom .011 to .047.
The MFX130, in Custom gauging, is built on round core wire wrapped with a silk-nylon and then finished with phosphor bronze wrap.
This design results in a sweet and melodic string with remarkable playability at any fret position. The high-quality carbon steel round core wire has high tensile strength to give the FX increased durability, allowing you to stay in tune and play longer. The round core wire and custom gauging also reduces finger fatigue and permits quicker transitions from string to string.
Users of the FX sets will note the increased sustain, brilliant attack and cleaner harmonic overtones.