In this schematic the "Nut" is used most often.
Parts such as the Rear Master Cylinder (gs750c: Clamp, Lock Washer, Yoke, Nut are included in the Gs750en 1978 (c) Usa (e03) Rear Master Cylinder (gs750c parts fiche.
The Rear Master Cylinder (gs750c is made up of components including this Cylinder Assembly,rear Master which is the most expensive.