One used 4 string set flatwound bass strings. They appear to be D'Addario with colored ball ends and blue wrap, but not sure of brand. They came off a used fretless I just bought, so they have no typical indent wear from frets. $12 shipped in the continental USA. 45 or 50 to 105 gauge. Cut to 34 inch scale length, Fender type headstock with all 4 tuners on one side.