The Martin MM11 Retro Monel Acoustic Guitar Strings are custom light strings designed for acoustic guitars. Made with high-quality Monel material and wound with a round wound winding, these strings offer a bright and clear tone that is perfect for fingerpicking or strumming. With a string gauge ranging from .011 to .052, these strings are ideal for guitarists looking for a versatile and durable option for their acoustic instrument. Made in Mexico, these strings are sure to enhance your playing experience with their rich and balanced sound. These are new old stock, never opened and factory sealed.