That's strange, my Arkym lip and diffuser fit awesome and are really nice pieces.
If this truly is an issue with the product and not just an adjustment issue, getting a replacement likely won't help because they are all produced using the same mold.
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2008 IB E92 M3| BBS | KW | Arkym | Platte Forme A.G. | Active Autowerke | K&N | Fabspeed | Dinan | Evolve-R
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