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2014+ BMW F32 4 Series M Performance Style Rear Diffuser
This is the PhaseOne M Performance style rear diffuser (non-carbon) for your F32 BMW 4 series.
This will fit any of the F32 generation BMW 420i, 428i, 430i, 435i, 440i as well as the xi and diesel variations.
Yes, it even fits the facelifted LCI F32 so don't you worry there!
The m performance package from BMW adds an aggressive front lip, side skirt extension, as well as rear diffuser to the already stylish 4 series.
Our PhaseOne performance style rear diffuser replaces the m sport diffuser so please make sure your vehicle is already equipped with the m sport package.
If not, have no fear, you can purchase one of our PhaseOne M sport style rear bumper conversions kits so you can have your cake and eat it too!
If quality, fitment, and durability is important to you, look no further than PhaseOne aerodynamics.
Our industry leading manufacturer uses some of the most cutting edge technology, coupled with over 20+ years of experience to craft the highest quality, best fitting body panels so that the conversion process is painless and the end result is simply beautiful.
PhaseOne kits are constructed using the same materials that OEMs use to manufacture their body panels.
- Bumpers are crafted using polypropylene thermoplastics, a highly durable and flexible material.
- Fenders are crafted from quality-grade steel.
The OEM engineers chose these specific materials for a reason right? Why risk using inferior parts that fall off the instant you go over a speed bump?
Only the best can wear the PhaseOne moniker.
Disclaimer: Although these kits can be installed on your own (DIY) we highly recommend that you utilize an experienced body shop to perform the labor. A professional body shop can be the difference maker between a good or bad result.
As best practice when looking for a shop, you should ask to see results of their previous work. If they claim to be experienced but have no tangible evidence, we would recommend caution when taking your business there. Kiesmotorsports is not responsible for poor labor practices.
If you have any questions or concerns, please don't hesitate to contact us. An informed / educated customer is a happy customer.
Your satisfaction is our priority, and we look forward to serving you!
We are typically very quick and have a 24-48 hour turnaround time. Transit time depends on your order and which warehouse we are shipping from, but typical transit times are between 5-7 business days from one side of the US to the other.
Majority of the items we offer do ship free to the lower contiguous 48 states. States that require plane or boat to reach (such as Hawaii, Alaska, Puerto Rico, etc) do NOT qualify for free shipping. Please contact us to inquire about international shipping costs. During checkout, you will know which items ship free and which have shipping costs associated with them. In general, larger/heavier items will have additional shipping costs (body kits, wheels/rims, etc)
Even though everything can be shipped internationally, sometimes the cost is simply just too high and doesn't make sense to do so. We're here to make sure you have a great shopping experience, so if you have a product(s) you want to inquire about, please contact us at firstname.lastname@example.org
Yes, we do price match reputable competitors in the marketplace. If you find a product cheaper elsewhere, please email us the (1) link of the product from our website and (2) the link to the competitor site. We will make an assessment on our end if we are able to price match or not and respond to you via email.
Typically you have 14 days to return a product you purchase when you change your mind. Damaged and improperly installed products are NOT eligible for returns. Shipping fees may be assessed and not refunded based on criteria as well as restocking fees. Please see our FAQ page for more details.
Unfortunate Kies Motorsports no longer does customer installs (with the exception of crank hubs - we still do thos inhouse). Our HQ is solely reserved for filming, office space, and shipping/receiving.