Last week, we shared a brief video showing that LG's revisions to the shielding in the UltraFine 5K display have successfully addressed issues with the display flickering and disconnecting when in close proximity to Wi-Fi routers. Apple and LG had temporarily pulled the display from the market while LG adjusted its manufacturing processes to incorporate the fix and push the new stock into sales channels, and sales of the revised display began earlier this month.

At the time of last week's post, we noted that customers purchasing the UltraFine 5K display should check for serial numbers beginning with 702 or 703, as these indicate manufacturing dates of February or March after the fix was put into place. Several MacRumors readers subsequently reported, however, that they have recently received units shipped from Apple with serial numbers starting with 612, indicating manufacturing dates in December 2016.

These readers have been uncertain as to whether their units have the revised shielding in place, or if they should be testing their displays to see if the flickering issue can be induced. One reader noticed that the label on the box of his December UltraFine 5K included a black circular sticker at the top left, a sticker that was not present on our original UltraFine 5K display that was manufactured in November and shipped in December and which was susceptible to the interference issue.

ultrafine circle square fixed

December 2016 unit retrofitted prior to sale (left) vs. March 2017 unit properly shielded from the start (right)

Newly manufactured UltraFine 5K units include a black square printed directly on the label in the same location, and LG has confirmed to MacRumors that the presence of a circle or square does in fact indicate that the unit has the revised internal shielding and should be protected from the interference issues.

While LG did not explicitly confirm any difference between a circle and a square, it appears that the square is indicative of a unit that was originally manufactured with the proper shielding, while the circle is used on earlier units that were subsequently retrofitted with the shielding before sale. There should be no difference in the performance of the two versions.

For those users with units lacking a circle or square on the label and thus susceptible to the Wi-Fi interference, LG is conducting free repairs to install the proper shielding. Users are advised to contact LG to arrange for the repair, which can take up to 7-10 business days once the display is received by the repair facility.

Customers interested in purchasing the UltraFine 5K should remember that Apple's 25 percent discount on USB-C and Thunderbolt 3 accessories is still scheduled to end on March 31, so they have just over a week to order the display at its discounted price of $974 before it goes back up to its regular price of $1299.95. It is possible Apple could extend the discount as it has done once already, but there are no guarantees.

Tag: LG
Related Forum: Mac Accessories

Top Rated Comments

craig1410 Avatar
115 months ago
That circle / square sticker thing seems to stack up. As expected, my 701s are both circles. But yeah, I still won't be returning them, as there are no obvious indicators now that these displays are inferior in any way to "square" models. Maybe when I go to sell these on eBay in 5 years, my dreaded "circle sticker" will knock $50 off the price though ;)

Still, it's dubious that LG / Apple are selling these circle models as "new". This is almost the very definition of manufacturer-refurb right? Apart from the fact that they weren't necessarily "returned" by customers (unless you count Apple as LG's customer). They've still been opened, refurbished in-a-sense, and repacked.
I think as long as they are "unused" then it's okay to sell as new, even if they were upgraded and repacked.
Score: 1 Votes (Like | Disagree)
Corrode Avatar
115 months ago
Thanks for writing about this. I pick up my fourth display (third replacement) tonight. Hoping for a square!
Score: 1 Votes (Like | Disagree)

Popular Stories

apple intelligence black

Report: Apple's AI Strategy Could Finally Pay Off in 2026

Tuesday December 30, 2025 9:01 am PST by
Apple's restrained artificial intelligence strategy may pay off in 2026 amid the arrival of a revamped Siri and concerns around the AI market "bubble" bursting, The Information argues. The speculative report notes that Apple has taken a restrained approach with AI innovations compared with peers such as OpenAI, Google, and Meta, which are investing hundreds of billions of dollars in data...
apple fitness 2026 1

Apple Teases 'Something Big' Coming Soon to Apple Fitness+

Tuesday December 30, 2025 2:11 pm PST by
The Apple Fitness+ Instagram account today teased that the service has "big plans" for 2026. In a video, several Apple Fitness+ trainers are shown holding up newspapers with headlines related to Apple Fitness+. What's Apple Fitness+ Planning for the New Year? Something Big is Coming to Apple Fitness+ The Countdown Begins. Apple Fitness+ 2026 is Almost Here 2026 Plans Still Under ...
maxresdefault

Hands-On With a Rough iPhone Fold Mockup

Monday December 29, 2025 10:55 am PST by
Apple is rumored to be introducing a foldable iPhone in September 2026, and since it will bring the biggest form factor change since the iPhone was introduced in 2007, curiosity about the design is high. A 3D designer created an iPhone Fold design based on rumors, and we printed it out to see how it compares to Apple's current iPhones. Subscribe to the MacRumors YouTube channel for more ...
maxresdefault

Where's the New Apple TV?

Monday December 22, 2025 11:30 am PST by
Apple hasn't updated the Apple TV 4K since 2022, and 2025 was supposed to be the year that we got a refresh. There were rumors suggesting Apple would release the new Apple TV before the end of 2025, but it looks like that's not going to happen now. Subscribe to the MacRumors YouTube channel for more videos. Bloomberg's Mark Gurman said several times across 2024 and 2025 that Apple would...
iphone 17 pro dark blue 1

iPhone 17 Pro and Pro Max Users Report Static Speaker Noise While Charging

Tuesday December 30, 2025 10:39 am PST by
iPhone 17 Pro and Pro Max owners are having trouble with the speakers of their devices, and have complained about a static or hissing noise that occurs when the iPhone is charging. There are multiple discussions about the issue on Reddit, the MacRumors forums, and Apple's Support Community, where affected users say there is a noticeable static noise "like an old radio." Some people report...
iPhone Top Left Hole Punch Face ID Feature Purple

iPhone 18 Pro Launching Next Year With These 12 New Features

Tuesday December 23, 2025 8:36 am PST by
While the iPhone 18 Pro and iPhone 18 Pro Max are not expected to launch for another nine months, there are already plenty of rumors about the devices. Below, we have recapped 12 features rumored for the iPhone 18 Pro models. The same overall design is expected, with 6.3-inch and 6.9-inch display sizes, and a "plateau" housing three rear cameras Under-screen Face ID Front camera in...
iOS 26

iOS 26.2 Adds These 8 New Features to Your iPhone

Monday December 22, 2025 8:47 am PST by
Earlier this month, Apple released iOS 26.2, following more than a month of beta testing. It is a big update, with many new features and changes for iPhones. iOS 26.2 adds a Liquid Glass slider for the Lock Screen's clock, offline lyrics in Apple Music, and more. Below, we have highlighted a total of eight new features. Liquid Glass Slider on Lock Screen A new slider in the Lock...
samsung glitter blue

Samsung's Year End Sale Introduces Major Discounts on Popular Monitors and TVs

Monday December 29, 2025 6:29 am PST by
Samsung kicked off a new end-of-the-year sale this week, introducing great deals on monitors, TVs, Galaxy smartphones, and home appliances. Many of these deals are the exact same all-time low prices we tracked during Black Friday and Cyber Monday. Note: MacRumors is an affiliate partner with Samsung. When you click a link and make a purchase, we may receive a small payment, which helps us keep ...
iOS 26 Glass Feature

The 5 Most Important Apple Software Features Introduced This Year

Tuesday December 30, 2025 1:00 am PST by
2025 was a significant year of advancement for Apple's software, with a noticeable focus on visual design, productivity, and communication. While Apple introduced and continued to iterate on a wide range of features throughout the year, several additions stood out for their scope and practical impact across multiple devices. As the year comes to an end, these five new features provide a...