Apple’s tagline for iPhone Duo is “Foldable. Posable. And durable.” Its press release backs the last word with a mirror-polished Grade 5 titanium frame, a hinge of more than 100 components with a 3D-printed titanium cover, Ceramic Shield 2 on the front, Ceramic Shield on the back, and an IP68 rating to a maximum depth of 6 meters for up to 30 minutes.
Two numbers foldable buyers usually ask for are still missing. Apple has not published a hinge cycle rating, and it has not published any measurement of the crease on the inner display. The phone is 5.2 mm thick open, 11.3 mm closed, and weighs 254 g.
IP68: 6 meters for 30 minutes
The IP68 rating covers both dust and water, and Apple’s specs put the water figure at 6 meters for up to 30 minutes. That is Apple’s published figure for a phone with a moving hinge, and Apple has not said anything further about how the hinge is sealed.
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The titanium hinge: 100-plus parts, 3D-printed cover
The frame is Grade 5 titanium with a mirror-polished finish, and the hinge cover is 3D-printed from 100 percent recycled titanium. Apple says the hinge has more than 100 components and uses custom adhesives for flex relief.
What Apple has not published is how many open-and-close cycles the hinge is rated for, how it was tested, or whether any warranty terms are specific to the hinge. We noted the same gap in our pre-keynote iPhone Duo preview, and the press release does not close it.
Ceramic Shield 2 in front, Ceramic Shield behind, polymer inside
The outer display sits behind Ceramic Shield 2, which Apple says offers three times better scratch resistance. The back is Ceramic Shield. That is the same front-and-back arrangement as a conventional iPhone, applied to the closed phone.
The inner folding display is different. Its cover is a custom polymer that Apple says has 40 percent higher stiffness than the industry standard, laid over high-strength glass layers, with a scratch-resistant coating on top. Apple has not said how that polymer’s scratch resistance compares with Ceramic Shield 2.
| Durability spec | iPhone Duo (Apple press release and specs) |
|---|---|
| Water and dust | IP68, 6 meters for up to 30 minutes |
| Frame | Grade 5 titanium, mirror-polished |
| Hinge | More than 100 components, custom adhesives for flex relief |
| Hinge cover | 3D-printed, 100 percent recycled titanium |
| Front (outer display) | Ceramic Shield 2, 3x scratch resistance |
| Back | Ceramic Shield |
| Inner display cover | Custom polymer, 40 percent stiffer than industry standard, over high-strength glass, scratch-resistant coating |
| Thickness and weight | 5.2 mm open, 11.3 mm closed, 254 g |
| Hinge cycle rating | Not published |
| Crease measurement | Not published |
The crease question
Apple says the nano-texture finish on the inner display “minimizes the visible crease”. The verb is minimizes, not eliminates, so Apple is acknowledging a crease exists and claiming the finish makes it less visible. The stiffer polymer cover is the other half of that claim, though Apple does not connect the two directly.
Apple has not published the crease’s depth or width, or any comparison with other foldables. CEO John Ternus called the Duo “the most transformational change to iPhone since the original” in the press release, but the crease is not mentioned in it.
Pre-orders open Friday, October 16, at 5 a.m. PT, with availability on October 23, and hands-on reports before then are the likeliest source of hinge and crease detail. For everything else Apple announced, see our event recap and the iPhone 18 Pro rundown.
