Robert or Karen Swarts wrote:
The brown synthetic material they make some sheaves, blocks, and winches out
of -- is it delrin? Anyway, the question is what can be used to refinish or
revitalize it as it begins to weather?

BS

It's probably a phenolic resin + fabric/glass reinforcement. I doubt
you could easily refinish, though maybe painting would work except on
the moving bits that have a line rubbing on them.

Evan Gatehouse