It's fuzz, flexible, soft, fits in my pants' squeegie pocket.
Not great for cleaning breaks during a game
I use it to do a final clean of my barrel after using another squeegie, and I use it to clean many parts of my marker, even when it's disassembled. I use it mainly for cleaning instead of while playing. I wouldn't recommend getting grit in it while you play, and you don't want to pull grit through your marker or barrel (ouch). I wash it out thoroughly and let it dry in my dish rack between days of play.