In this schematic the "Washer,oil Bolt" is used most often.
The most reasonably priced component used on the Gl1500a Goldwing Aspencade 1993 (p) Finland / Kph Rear Brake Master Cylinder is the Screw-washer 4x14.
Parts such as the Rear Brake Master Cylinder: Bolt,flange,6x12, Push Rod Comp., Switch Assy.,rr.s, Hose,rr.m/c are included in the Gl1500a Goldwing Aspencade 1993 (p) Finland / Kph Rear Brake Master Cylinder parts fiche.