Unweaving the Mystery: Apple’s FineWoven Case Under the Microscope
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Unweaving the Mystery: Apple’s FineWoven Case Under the Microscope

Apple didn’t just announce some new electronics this year—they also unveiled a new fabric. Will it revolutionize the gadget landscape forever? Perhaps not. But it does feel pretty nice, and we thought it merited a closer look. A lot closer.

To make that happen, we’re adding a new tool to our workbench: a very fancy digital microscope, courtesy of Evident Scientific. It’s the perfect tool to take a closer look at this new-fangled FineWoven material. Join us as we zoom and enhance the new iPhone FineWoven case!

A finely woven fabric

Here’s an iPhone 15 Pro case with FineWoven fabric:

Here’s what that FineWoven fabric looks like under 52x magnification:

Image of the FineWoven fabric iPhone case at 52x zoom
Organized bundles of tightly woven fibers. Magnification: 52x

…and under 490x magnification:

FineWoven fibers, with a strand of hair for scale. Magnification: 490x

The fabric lives up to its name—those individual fibers are fine! They measure about 6 microns thick (or 0.00024 inches)—that’s about 1/12 the width of a human hair (the pictured hair strand is 72 microns wide). Groups of these fibers make up threads that are approximately 150 microns thick. Most of us don’t have an intuitive feel of tight-woven fabric density, so for comparison: sheets made out of FineWoven fabric would have a 340 thread count, or 170 threads per inch per direction. But, that’s not really the right comparison, since each thread is made of many fibers rather than a single strand.

Apple noted that FineWoven is a microtwill. Twill is a weave that creates a pretty, diagonal pattern. We scampered around our office stealing outerwear from our team and put all the fabric we could find under the microscope in search of something similar to FineWoven. Success! The Arc’teryx Atom LT jacket and Patagonia TechFace jacket (which happens to also use recycled materials) both have similar construction. 

Left: FineWoven fabric. Center: Arc’teryx jacket fibers. Right: Patagonia jacket fibers. The Patagonia jacket has a bigger/looser weave. Magnification: 440x
Left: FineWoven fabric. Center: Arc’teryx jacket fibers. Right: Patagonia jacket fibers. The Patagonia jacket has a bigger/looser weave. Magnification: 440x

Testing the fabric

The FineWoven fabric looks great—as long as you don’t touch it. But, what if you do? What if you scratched the fabric with a key or fingernail?

The key mars the surface less than a fingernail because the key contact area is bigger.

Because the weave is so tight, the FineWoven fabric should be pretty durable and tear-resistant. However, since its threads are so fine, it’s also very easy to mar the pristine weave. When we scratched the surface, the jostled threads didn’t actually break, nor was the dye damaged. Rather, the scratch-jostled fibers reflect light irregularly compared to the untouched bunches, creating a lasting visual mark. The thread itself is relatively soft, so most pocket items will leave an impression.

Left: “keyed” fibers show very little damage. Center: fibers sliced with a knife, showing actual fiber damage. Right: Fingernailed fibers suffering heavy jostling. Magnification: 240x

Will it stain, or will it be Fine?

But how do these super fine fibers handle liquids, greasy hands, or, say, hot sauce? Let’s take a look:


The FineWoven fabric gulped down the coffee like a college student in a 7 AM class. Unlike the Arc’teryx or Patagonia jackets, the case doesn’t have a Durable Water Repellent (DWR) treatment. A DWR treatment adjusts the surface tension properties of the fabric, encouraging liquids to bead and roll off rather than soak into the fibers. The downside of DWRs is that they often contain polyfluoroalkyl chemicals (PFAs), which the EPA describes as “persistent, bioaccumulative, and toxic”.

Thankfully, the coffee evaporated from the case without leaving much of a trace.

FineWoven phone case with coffee dripped on it at normal and (right) 700x zoom
Coffee soaking into the fibers. Magnification: 700x


We smushed an extra greasy finger onto the case, and the resulting mark is there to stay. The oil saturated the fibers and changed the optical qualities, resulting in a dark-looking stain. We tried scrubbing the spot with detergent and managed to lighten the spot, but it’s still visible.

FineWoven phone case smeared with oil at normal and (right) 700x zoom
That dark spot isn’t a shadow. Right: The FineWoven fibers glisten from the oil bath. Magnification: 700x

Hot sauce

What if you accidentally placed the phone on a dirty table after hosting a Hot Ones party? Bad news: the FineWoven fabric can’t handle the heat. The hot sauce’s vinegar soaked in and marred the fabric.

Left, an iFixit Jimmy scraping barbecue sauce off an iPhone case, right a 700x zoom image of barbecue sauce on FineWoven fibers
It doesn’t matter how mild the hot sauce is—it will leave a mark. Magnification: 700x

The rest of the case

Now that we’ve completed the dirty work, let’s cut to the chase and see how it’s layered. 

A kitchen knife cutting an iPhone case on a butting board
A cross section of a FineWoven case cut in half
That’s a lot of filling in those thin sandwiches!

From exterior to interior, the case layers are stacked as follows: FineWoven fabric, gray foam, rigid plastic sheet, MagSafe hardware/white foam, another rigid plastic sheet, and finally, an inner layer of FineWoven fabric.

The layers of a FineWoven case peeled up
Each layer is firmly glued to its neighbors.

As expected, the FineWoven fabric layer is very thin—about 0.17 mm. Unlike leather, a woven fabric’s thickness is highly dependent on how thick the thread is. The thinner the thread, the thinner the fabric.

Given the foam and adhesive, the fabric is likely even thinner.

We burned a bit of the FineWoven fabric to suss out more of its properties. The material gave out a sweet smell and left a sticky, black, mass. This makes us think that it’s likely a polyester-based material. 

The side rails look like plastic, but they actually have a FineWoven weave. The fibers have been coated with a kind of resin, resulting in a hard, non-porous surface. 

The FineWoven material on the side rails is more durable. Magnification: 240x

End of the thread…

FineWoven is truly fine, and a really neat, high-end material, with fibers as small as 6 microns. The tight weave makes the fabric somewhat wear-resistant, but nicks and marks will show and stay. Unfortunately, without the additional protection found in technical garments like TechFace, it’s not liquid-proof. You’ve either got to be very careful with where you set the case, or treat it with a DWR or fabric protector like Scotchgard yourself. 

Some more loose ends

We also tore down the iPhone 15 Pro Max and Apple Watch Ultra 2!

We snapped some high-quality imagery that might make stellar—if small— wallpapers. Don’t worry, no hot sauce in these shots. You won’t be able to feel the fabric through the screen, but these digital immortals won’t get scratched up. 

FineWoven “Wallpapers”