Can't seem to know who makes them for Zon. I never called Zon but everyone I ask has no idea. I think they sound kind of nice. They are bright and last a fairly long time. I had used them before on my Sadowsky 5. Recently I picked up a Alleva Coppolo LM5 which sounds Unbelievable. But I am curious about there strings. I don't think they themselves make them. Got to be one of the few companies that do.