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
113 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
113 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 store down feature

Here's Why the Apple Store is Going Down

Thursday November 27, 2025 1:01 pm PST by
Apple's online store is going down for a few hours on a rolling country-by-country basis right now, but do not get your hopes up for new products. Apple takes its online store down for a few hours ahead of Black Friday every year to tease/prepare for its annual gift card offer with the purchase of select products. The store already went down and came back online in Australia and New Zealand, ...
Apple Foldable Thumb

Foldable iPhone to Debut These Three Breakthrough Features

Tuesday November 25, 2025 7:09 am PST by
Apple's first foldable iPhone is expected to launch alongside the iPhone 18 Pro models in fall 2026, and it's shaping up to include three standout features that could set it apart from the competition. The book-style foldable will reportedly feature an industry-first 24-megapixel under-display camera built into the inner display, according to a recent JP Morgan equity research report. That...
iPhone Pocket Short

iPhone Pocket is Now Completely Sold Out Worldwide

Tuesday November 25, 2025 7:16 am PST by
Apple recently teamed up with Japanese fashion brand ISSEY MIYAKE to create the iPhone Pocket, a limited-edition knitted accessory designed to carry an iPhone. However, it is now completely sold out in all countries where it was released. iPhone Pocket became available to order on Apple's online store starting Friday, November 14, in the United States, France, China, Italy, Japan, Singapore, ...
streaming black friday 2025

Black Friday Streaming Deals Include Big Savings on Disney+, Hulu, Apple TV, and More

Monday November 24, 2025 8:03 am PST by
We've been focusing on deals on physical products over the past few weeks, but Black Friday is also a great time of year to purchase a streaming membership. Some of the biggest services have great discounts for new and select returning members this week, including Disney+, Hulu, Paramount+, Peacock, and more. Note: MacRumors is an affiliate partner with some of these vendors. When you click a...
streaming black friday 2025

Best Black Friday Streaming Deals - Save Big on Apple TV, Disney+, Hulu, and More

Thursday November 27, 2025 1:14 pm PST by
We've been focusing on deals on physical products over the past few weeks, but Black Friday is also a great time of year to purchase a streaming membership. Some of the biggest services have great discounts for new and select returning members this week, including Apple TV, Disney+, Hulu, Paramount+, Peacock, and more. Note: MacRumors is an affiliate partner with some of these vendors. When...
General Black Friday Deals 25 Red Green

The 30+ Best Black Friday Apple Deals on AirPods, iPads, MacBooks, and More

Thursday November 27, 2025 6:46 am PST by
Black Friday is in full swing, and as always this is the best time of the year to shop for great deals, including popular Apple products like AirPods, iPad, Apple Watch, and more. In this article, the majority of the discounts will be found on Amazon. Note: MacRumors is an affiliate partner with some of these vendors. When you click a link and make a purchase, we may receive a small payment,...
General Apps Messages Redux

Singapore Orders Changes to iMessage by December

Tuesday November 25, 2025 6:39 am PST by
Singapore has ordered Apple to block or filter messages on iMessage that impersonate government agencies, requiring the company to implement new anti-spoofing protections by December as part of efforts to curb rising online scams, the Straits Times reports. Singapore's Ministry of Home Affairs (MHA) said that it had issued an Implementation Directive to Apple under the Online Criminal Harms...
iphone air camera

iPhone Air Flop Sparks Industry Retreat From Ultra-Thin Phones

Thursday November 27, 2025 3:14 am PST by
Apple's disappointing iPhone Air sales are causing major Chinese mobile vendors to scrap or freeze their own ultra-thin phone projects, according to reports coming out of Asia. Since the ‌iPhone Air‌ launched in September, there have been reports of poor sales and manufacturing cuts, while Apple's supply chain has scaled back shipments and production. Apple supplier Foxconn has...