Quick view M4 Flat Washers, DIN 125 Type B / ISO 7090, Steel The nominal diameter is the bolt size to use for this flat washer.Diameter (Nominal): M4Inside Diameter (Nominal): 4.3mmOutside Diameter (Nominal): 9mmThickness (Nominal): 0.8mmProduct Class: WashersOrder: Flat WashersCategory: Standard Flat... $182.18 Select Quantity Compare