Joseph Dresselhaus 3631/000/01 4,3 large-diameter fender washer (penny washer) to DIN 9021, for M4 bolts, A4 stainless steel. Spreads load over thin or oversized-hole material. Manufacturer's own designation: Joseph Dresselhaus 3631/000/01 4,3 Inner diameter: 4,3, Outer diameter: 11, thickness: 0,8, for bolt size: M4.