Historic stainless flatwound guitar strings in gauges 13-17-26w-36-46-56. Great for jazz, but also used for many other styles of music.
Great strings in terms of feel, sound, and intonation. They are warmer than D'addario, with a grittier feel like GHS or DR flatwounds. I prefer this kind of texture. They are a traditional 13-56 set with a 26 for the g (unlike thomastik which are thinner for the g, d, a strings). when you find the sweet spot with the bridge and truss rod on an arch top, they have the right amount of tension and acoustic volume. These are right in there with the top flat-wounds.