so they have the removeable steel edge blades like the lopro and original edge? to my knowledge even the original and lo pro were made from pot metal with only the blades being steel as well. If this is the case does the zr2 also have steel knife edges?
The knife edges are "steel", but no more information is given and while supposedly "removable/replaceable" it's not something you'd easily and regularly be able to do. It's such a process that Gotoh doesn't technically sell the replacements.
The ZR series use bearings not knife edges.