Output Flange Collar Nut (M20x1.5mm) - 1600/2000 (67-71) (use 30mm socket) (1 available) . Similar to 33121200258 except the flange diameter is approx 36mm for this nut and approx 40mm for the "258" nut that fits the more powerful cars.
Note- I stock the Facom S.30LA socket for the R&R of this nut.