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SpeedForm Sport Quarter Window Louvers; Gloss Black (15-23 Mustang Fastback)

Item 403357
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Market Price $64.99 You Save 12% ($8.00)
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$56.99 (pair)

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      Video Review & Installation

      Hey, guys. Today we're gonna be taking a look at and installing the SpeedForm Sport Quarter Window Louvers in gloss black for 2015 and newer Fastback Mustangs. So, quarter window louvers aren't for everyone, but they are a very quick, easy, and non-permanent way to modify your car and give it your own look. They're for someone looking for a bold exterior styling piece on a budget. They're very budget-friendly, costing right about 50 bucks. These come gloss black already, so you don't have to worry about sending them out to be painted, and they'll match any color Mustang. They can be paint matched though if you guys wanted to. They're Chevron-shaped quarter window louvers to work with the body lines of the car, and they're made of ABS, which means that they're lightweight and durable. So, they're perfect for exterior pieces. Now, the underside of these is not finished though, so if you guys are worried about the looks from the inside of the car, you can always grab some quarter window blackout decals so then you won't see it. As far as the install goes, I am gonna call it a very easy one out of three wrenches on the difficulty meter. And we'll go ahead and show you how I got these on the car.For this install, you'll use an alcohol prep pad, a pair of scissors, a rag, and soap and water.All right, guys. So, the first step of your install is actually gonna be to clean your quarter window with warm soap and water. You're gonna wanna make sure you clean everything off of it, any dirt, any bugs, any Windex, anything that's gonna make the 3M tape not stick well to your window. So, we've already done that. You're gonna wanna make sure that you give it ample time to dry. You don't want any moisture or any wetness. You're also gonna wanna make sure that you're at an appropriate temperature too, because you don't want the window to be ice cold when you go to install the 3M tape. You're gonna wanna be looking more in the 50, 60-degree range at least in order for the 3M tape to adhere properly.So, our next step, which we're gonna do right now is we're actually gonna flip the louver over, and we're gonna apply our supplied 3M tape to the backside of it. So, basically, what we're gonna do is we're gonna go around the entire perimeter of the louver with the 3M tape. I have a pair of scissors here. Basically, just going to peel it back, start measuring a little bit, just line it up, and then we'll cut the piece of 3M and stick it onto the louver. So, while I'm doing this, you guys can get a really good view of the underside of the louver. And I will say that if you're not in love with the unfinished side of the louver here, you guys can see it's more of a raw finish, it's not painted on the underside, you guys can always pick up a set of quarter panel blackout decals, and that's gonna be a decal that will go over your quarter window before you install the louver. And it's just a black decal. And what it's gonna do is keep you from seeing this underside of the louver from inside of your car. So, it went a little over, so I'm gonna cut this piece off, because you don't really want anything sticking out. Get yourself some good scissors. I'm gonna make sure this is sticking to the back of the louver nicely, because this is what's gonna hold the louver onto your car. Another thing that you guys can do to prep the glass if you want to is you can take a little bit of alcohol and clean your window with the alcohol, and that's really gonna make sure you don't have any Windex or anything that's gonna interfere with the 3M tape on there.All right. So, our next step with this louver is we are going to peel the backing off the 3M tape here, and we're gonna get ready to apply it to the car. So, I'm just going to use my fingernail, get under the corner and peel the backing off. All right. So, like I talked about earlier, I'm gonna take an alcohol prep pad, and I'm just gonna go around the outside of my window here where the 3M is gonna be making contact with the glass. Just wanna make sure it's as clean as possible. That means no Windex, no wax, no polish, no nothing. Now, we'll take our louver, we're gonna line it up with the window and stick it in place. Just being very careful here. I'm not allowing the 3M to touch the window just yet until I have it lined up perfectly. All right. And now that it's all lined up, what I'm gonna do is I'm going to just press this into place. Then I wanna make sure that you give pressure everywhere that the 3M is, and you're also gonna wanna make sure you don't take your car through any car wash for a day or two. You don't wanna give it a bath either. You wanna make sure that you give this 3M every chance to adhere properly. You'll do the exact same thing for the other side now.All right, guys, that's gonna wrap up this review and install. Keep in mind that you can always check these out more online right here at

      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation


      • Chevron Shaped Louvered Design
      • Gloss Black Finish
      • Vacuum Form ABS Construction
      • Simple Peel and Stick Installation
      • Driver and Passenger Side Louvers Included
      • Fits all 2015-2023 Fastback Mustang Models


      Sporty Styling. A pair of SpeedForm's Gloss Black Sport Quarter Window Louvers are a quick and easy way to add sporty styling to the exterior of your 2015-2023 Fastback Mustang. Featuring a louvered chevron design, these C-Pillar Window Louvers will enhance the bold styling of your S550 Pony's body lines.

      Quality Construction and Materials. SpeedForm's Sport Quarter Window Louvers are manufactured from vacuum-formed acrylonitrile butadiene styrene (ABS) plastic for its light weight and long lasting durability. These Quarter Window Louvers are then completed in a smooth gloss black finish for aggressive good looks.

      Peel and Stick Installation. No messy glue or drilling is required for installation. These SpeedForm Sport Quarter Window Louvers are designed to attach to the factory C-Pillar glass with the supplied 3M doubled sided automotive bonding tape for a quick and easy installation. Just clean the surface, peel the backing and stick in place - it's that easy.

      Recommended Styling Upgrade. When installing exterior quarter window louvers or scoops on your Mustang, it is recommended to add a set of quarter window blackout decals to hide the ugly back side that wasn't meant to be seen by human eyes. See part number 386505.

      Application. These gloss black SpeedForm Sport Quarter Window Louvers are designed to fit all 2015-2023 Fastback Mustangs, including the V6, EcoBoost, GT, GT350 and GT500 models. Sold as a set of two, one driver side and one passenger side.




      SpeedForm 403357

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Passenger Side - Quarter Window Louver
      • (1) Driver Side - Quarter Window Louver
      • (1) Roll of Automotive Bonding Tape

      Customer Reviews (193)

        Questions & Answers

        10 More Questions

        Will It Fit My Mustang

        • Bullitt - 19, 20
        • EcoBoost - 15, 16, 17, 18, 19, 20, 21, 22, 23
        • GT - 15, 16, 17, 18, 19, 20, 21, 22, 23
        • GT350 - 15, 16, 17, 18, 19, 20
        • GT350R - 15, 16, 17, 18, 19, 20
        • GT500 - 20, 21, 22
        • Mach 1 - 21, 22, 23
        • V6 - 15, 16, 17

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