Used string set. I usually replace them every 1-2 years. This set was replaced after one year of use. While there may be some slight roughness, I believe they are still usable. Those who like the mellow sound of Spirocore, where the initial brightness has settled down, should definitely check these out! I switched to light tension strings, so I'm selling several sets of medium strings that I replaced, which I had at home, on Mercari! Due to the nature of used items, no claims or returns are accepted to prevent swapping! I will ship them together in one bag! - Brand: Spirocore - Instrument Type: Contrabass - String Type: Spiral Core - Gauge: Medium - Thank you for looking.