BMW Copper Lock Nut 10 mm Exhaust Flange e10 e21 e23 e28 e30 e32 e34 e36 e46 e90 Copper Lock Nut 10 mm Exhaust Flange (set of 4) Brand NEW part with full 1 year warranty. BMW part# 18 30 1 737 774, check fit below. Recently made O.E.M. part, not been lying around. NOTE: X5 fits 3.0i only.