On this parts fiche the Washer(10x15x1.5) is the most specified component.
Parts such as the Front Brake Hose: Cap(od:12), Adapter,brake Hose, Guide,brake Hose, Union are included in the Vs1400glp 1991 (m) (e01 E04 E17 E21 E22 E34 E39) Front Brake Hose parts fiche.
This schematic depicts all components used in the Vs1400glp 1991 (m) (e01 E04 E17 E21 E22 E34 E39) Front Brake Hose partslist.