SKU: 55298569416

Flow Designs GT Mustang S550 FN Flow-Lock Rear Diffuser

Sale price$171.00 Regular price$190.00
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Ships within 48 hours · Estimated delivery Aug 20 - Aug 25

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Description

Flow Designs GT Mustang S550 FN Flow-Lock Rear DiffuserSuits 2018+ Ford Mustang GT S550 FN INSTALL DOES NOT REQUIRE REAR BUMPER REMOVAL For rear valance without Flow Lock fins click here. Details Experience Flow Lock rear diffuser for your Mustang S550 FN, sharing the same durability and technology as our renowned WRX, Golf GTI & MK3 Focus RS line up which is trusted by car enthusiasts worldwide. The rear valance and diffuser fins will clear the Mustang S550 FN dual exhaust tips with ease, and rear bumper


Suits 2018+ Ford Mustang GT S550 FN

INSTALL DOES NOT REQUIRE REAR BUMPER REMOVAL

For rear valance without Flow-Lock fins click here.


Details

Experience Flow-Lock rear diffuser for your Mustang S550 FN, sharing the same durability and technology as our renowned WRX, Golf GTI & MK3 Focus RS line up which is trusted by car enthusiasts worldwide. The rear valance and diffuser fins will clear the Mustang S550 FN dual exhaust tips with ease, and rear bumper removal is not necessary for installation of the diffuser. 10 year warranty applies for the rear valance (excludes ABS fins).

The Flow-Lock interlocking system allows for the final assembly of the diffuser fins without tools or fasteners. A simple push and click and the kit is assembled and ready for installation - this means zero exposed hardware giving you the cleanest look for your Mustang S550 FN rear. 

No more L-brackets, no additional exposed hardware and no double-sided tape, experience the Flow-Lock difference today!
 

Valance is installed to the car through bolts and nuts while the Flow-Lock diffuser fins simply click into the valance (once locked into the valance it is secure). It is also possible to install when your car is on the ground.


Kit Includes:

  • Mustang S550 FN rear valance
  • Mustang S550 FN Flow-Lock diffuser fins
  • 2 Flow Designs stickers
  • Fitting kit

Material & Finish:

  • Valance: 10mm thick polyethylene composite, bevelled edges
  • Flow-Lock diffuser fins: 4.5mm thick textured ABS 
  • Valance: Finish available in gloss black, or scratch-resistant textured matte black
  • Flow-Lock diffuser fins: scratch resistant textured ABS plastic
  • CNC engraved logo and features

Install Instructions (PDF)

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 55298569416

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4.4 ★★★★★
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A
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Amazon Customer
Houston, US
★★★★★ 5
Comparable to high end mens shops!
Fit Type: Regular Fit, Color: Blue, Size: Large
Beautiful, heavy blue Oxford comparable to upper end mens store at 75% less! Full cut, great for casual wear or sending out for professional starching. Downside, no pocket, but I had mine monogramed wear the pocket would be and it looks like an expensive dress shirt. I bought more (with pockets) in blue & white
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 3, 2026
A
Verified Purchase
Anon
Lexington, US
★★★★★ 3
Heavier fabric, very durable
Fit Type: Regular Fit, Color: Grey, Size: Large
3 stars. Pretty nice shirt but the fabric is a bit firmer than i like. I iron it when i usually wear it so that it looks half decent since wrinkle resistance is low or poor. I usually have to use a higher setting on the fabric since the material is thick making it alot heavier. Overall great for the lower end cost, anything that beats it would probably be double the price. I work in a cubicle so this works well for me, a simple shirt, with a simple color.
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Reviewed in the United States on March 18, 2026
M
Verified Purchase
MMongelli
Port Orchard, US
★★★★★ 5
True to size, good quality, great value!
Fit Type: Regular Fit, Color: White, Size: Medium
Great quality! Amazing thick material! Perfect basic button down shirt!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 14, 2025
E
Verified Purchase
Ed
Charlottesville, US
★★★★★ 4
No Shirt Pocket!
Fit Type: Regular Fit, Color: Blue Stripe, Size: X-Large
No Pocket! The material was nice quality, a little thicker than I would have anticipate for a low priced shirt, and very soft. The only disappointment was there was not shirt pocket. I suppose I did not look closely enough at the photos to notice that before I purchased. Otherwise, this is a very comfortable shirt.
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Reviewed in the United States on February 23, 2026
M
Verified Purchase
Monica cable
Alexandria, US
★★★★★ 5
Great shirt
Looks so good on hubby he likes the fit very comfortable
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 27, 2026

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