D.I.D.'s 428NZ chain is a non O-ring chain with solid bushing and quad-riveted pins. D.I.D.'s SDH high-tech pin treatment forms an extremely hard chromium carbide layer on the pin's surface while maintaining a softer inner core. SDH treated pins have extreme impact strength while adding outstanding shock absorption. The SDH process creates a chain with superior wear resistance, outstanding anti-oxidation properties and performs well in dusty and muddy conditions.