In this schematic the "Washer,oil Bolt" is used most often.
The lowest price component in this Fr. Brake Master Cylinder parts-list fiche is the Screw,flat,4x12.
A sample from the products for the Fr. Brake Master Cylinder include: Nut,cap,6mm, Lever Assy.,r.han, Washer,oil Bolt, Sw Assy,fr Stop.