Thomastik contrabass strings, A string and E string. (For the solo high-pitched side. Note) These strings were originally on the contrabass I received, and based on the ball-end color and the previous owner's story, I suspect they are Belcanto solo strings. I used them on a full-scale contrabass. Used for over a year. (How long the previous owner had them on is unknown) I used the solo strings (E, A) in normal tuning (G, D). Both the previous owner and I only used them for jazz, and we never played arco, so there are no rosin marks, and they are in relatively clean condition. After use, I wiped off any body oils and regularly maintained them with String Life. Therefore, the surface is still shiny. I hardly feel any roughness. (This is my personal impression.) However, since they were used normally, there are creases and winding marks. This time, I replaced them because I felt the sustain had decreased. They are still in usable condition, so I will give them to someone who wants to try them. Compared to the newly strung Spirocore, they have a warm and gentle tone. Since I cannot track these by serial number, returns are not accepted.