Chrome stainless steel frame, Alconite insert ring. The "K" series concept guides are the first rod guides designed to "shed" tangles before they become a problem.
The newest edition to the Fuji K series the K-Revolution "H" guides feature the same sloped ring as the traditional tangle free K-Series Guide, but feature a smaller ring atop a much higher frame.
KR Series guides are designated with an "H" following the guide Size