The Washer, Oil Bolt is the most widely applied product in the VT1100C2 SHADOW 1999 (X) FINLAND / KPH RR. BRAKE MASTER CYLINDER ( four times ).
Some items from this specific schematic: Sub Assy,rear M/c, Col Tank Setting, Joint,brk Rod, Hose Comp,rr Brk.
The Screw-washer,4x12 is the lowest priced item on this Rr. Brake Master Cylinder schematic.