These are nylon strings. They've been used for three years, so I've marked their condition as poor. Only the D and G strings are available. They show signs of use, but there are no noticeable scratches. The rubber piece in the 5th image is missing. You might want to cushion it with something. (Important!) I think they're usable, but since they've been strung for three years, then loosened and restrung, I can't guarantee anything, so please understand that they are NCNR (no claims, no returns)! Please only purchase if you're okay with taking a chance! The reason for selling is that I replaced all the strings with new ones because the A string broke. The set cost 26,000 yen at Sound House. Gut-a-Like Swingmaster strings are recommended for double bass players who often play pizzicato in jazz. These strings are made of nylon material that replicates the feel of gut strings, and they work well for both strokes and slaps. The surface is polished for durability and resistance to dirt.