DIN 137-A wave washer (form A), 1.8 x 4 x 0.25 mm, Article number 137A018. Property class / material: steel, surface finish plain. Wave Washer manufactured to DIN 137. 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.