ISO 7089 round flat washer, 28 x 50 x 5 mm, Article number 7089280. Property class / material: steel 200 hv, surface finish plain. Round Flat Washer manufactured to ISO 7089. Standard parts to the same standard, property class, dimensions and surface finish are interchangeable between manufacturers; confirm the controlling standard revision, any class-society or application approval, and the mating thread before substitution. Applications: load distribution and locking under bolt heads and nuts in machine building, structural steel, plant maintenance and marine outfitting.