Check out any of the eight Cylinder components enlisted.
Parts such as the Cylinder: Bolt,stud, Stud 6x20, Nut, Bolt,stud are included in the Tu250x 1997 (v) (e02 E04 E17 E24 E25 E34 E39) Cylinder parts fiche.
This CYLINDER assembly utilises four Bolt,stud(s) - the highest specified component.