Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 6 - Jul 11
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For Your Every Summer RSVP, with Code: SUMMER15
Description
ROUSH 2015-2017 Ford Mustang ACTIVE Exhaust Upgrade Kit (Requires ACTIVE-READY Exhaust Kit)Convert your ROUSH Quad Tip exhaust to a full Active exhaust and take control of your Exhaust note. Our Active Exhaust upgrade kit makes any 2015 2023 Active Ready quad tip exhaust system into an active exhaust that allows you to tune your exhaust note using our iOS application for virtually infinite sound possibilities. The system utilizes an easily installed valve system that adjusts the flow of the exhaust, thereby adjusting tone and volume. Plug
Convert your ROUSH Quad Tip exhaust to a full Active exhaust and take control of your Exhaust note. Our Active Exhaust upgrade kit makes any 2015-2023 Active Ready quad-tip exhaust system into an active exhaust that allows you to tune your exhaust note using our iOS application for virtually infinite sound possibilities. The system utilizes an easily installed valve system that adjusts the flow of the exhaust, thereby adjusting tone and volume. Plug and play Installation requires no cutting or welding. Included in the kit is a 4 mode selector knob with faceplate so you easily switch to pre-set and custom modes on the fly.Converts the following ROUSH Active Ready Quad Tip Exhaust Systems to Full Active Exhaust Systems: 5.0L V8 Active Ready Exhaust Part #421921 2.3L I4 Active Ready Exhaust Part #421923This Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2015-2023 | Ford | Mustang | EcoBoost |
| 2022-2023 | Ford | Mustang | EcoBoost Premium |
| 2015-2023 | Ford | Mustang | GT |
| 2022-2023 | Ford | Mustang | GT Premium |
| 2022-2023 | Ford | Mustang | Mach 1 |
| 2022 | Ford | Mustang | Shelby GT500 |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- 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
4.1 ★★★★★
Based on 1046 reviews
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Product Reviews
★★★★★ 5
GREAT!
Color: Multicolor-4pack-a1, Size: XX-Large
So comfortable and soft. I love them! No elastic. Sizes were accurate.
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Reviewed in the United States on May 22, 2026
★★★★★ 5
10/10
Color: Multicolor-4pack-a1, Size: Small
These are some of my favorite underwear. I find myself reaching for these constantly. They're very good quality and very stretchy. I'm 140 5'3 and I got a small they fit great. Someone larger or smaller would fit in the small too. I do stress that the leg holes are a bit tight on my thighs and I don't have thick thighs at all. On someone with thicker thighs I'd say size up to a medium. You can wear these as mid/high waisted or low waisted. They're versatile! The cotton gusset is a plus too❣️
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Reviewed in the United States on May 17, 2026
★★★★★ 5
Better than Haynes at for less money
Color: Multicolor-4pack-a1, Size: XX-Large
I am surprised by the quality of these knickers. They are better than Haynes for less money and when I say they’re better, I mean far better, but I can’t believe how comfortable and STRETCHY best underwear is
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Reviewed in the United States on April 25, 2026
★★★★★ 5
love love love!!
Color: Multicolor-4pack-a1, Size: Medium
like my daily driver now, like i never thought underwear could be this good untill now! have bought 2 4packd and will probably get more in the future :) they are snug but not suffocating, with my darker skin i was worried of them getting darker in that area but so far(3-4 months) they’ve been holding up well and clean easily in the washing with a bit of stain remover!
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Reviewed in the United States on May 19, 2026
★★★★★ 3
Satisfactory
Color: Multicolor-4pack-a1, Size: X-Large
If your wanting an easy on high waisted underwear these work.
They are honestly strange material, a mix of three different things- not bad but different.
Not seamless, might ride up, slightly on the thicker side. Will last a while. Comfortable enough but not amazing.
Got for after a surgery and needed something different- these worked but would I get on a normal day probably not.
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Reviewed in the United States on May 15, 2026