Historic stainless flatwound guitar strings in gauges 11-15-24-32-42-52. Great for jazz, but also used for many other styles of music.
Benefits of Flatwound Strings:
-Consistent tone over the life of the strings
-Less Fret wear
-Smooth surface causes less "squeaking" and easier on fingers
-Mellow sound
-Last longer than round wound strings, trade off in price.