M7 Exhaust Manifold Nut Head Stud Lock Nuts. BMW 3 Series E30, E36, E46, E60, E61, E81, E87, E88, E90, E91, E92, X1, X3 & X5. Copper Plated Hex nut with flange, self locking. Copper Hex Nut. No fitting instructions are provided with the product.
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