Spring seat

The present invention provides a workpiece (10) having a blind bore (12) of stepped form defining a chamber (16a, 16b) within which a seating member (14) is arranged. A region of the seating member (14) is shaped to form an interference fit within a first part (12a) of the bore (12), the shaped region of the seating member (14) being provided with one or more relieved sections (18) to ease insertion of the seating member (14) into the bore (12) during assembly of the workpiece (10). Cooperation between the seating member (14) and the first part (12a) of the bore (12) serves to retain the seating member (14) in position within the bore (12). The invention is particularly suited to being a nozzle holder body for a nozzle body of a fuel injector.