The Nut,flanged,6mm is the cheapest item from this partsfiche.
In this schematic the "Damper" is used most often.
Parts such as the Accessory(single Seat Cover): Bracket, Damper, Damper, Collar,6.8x10(16)x6.6 are included in the Ex300bhfa Ninja 300 Abs 2017 Europa,middle East,africa Accessory(single Seat Cover) parts fiche.