SWA-4-8-2-AW NBK Adjust Metal Washer - Steel NBK Adjust Metal Washer - Steel - Ferrosoferric Oxide Film Pack of 10 Washer Made in JapanSWA 4 8 2 AW NBK Adjust Metal Washer Steel Main body Black (Ferrosoferric Oxide Film S45C) Pack of 10 Washer NBK Made in Japan Characteristics: There is a variety of outside diameters and thickness relative to normal plain washers. For securing seating surface on the long hole position and engagement of materials with low marginal seating surface pressure such as aluminum and resin. As a collar and a spacer, it can adjust the cumulative error in