What Are the Specifications?

What Does the Package Include?

This  portable monitor is packed in a generic box that is made of hard cardboard and feels sturdy, so the monitor is well protected and should have no trouble surviving the usual shipping challenges.

You'll find everything will be in the box:

• Two USB-C to USB-C cables
• A Mini-HDMI to HDMI cable
• A 30 W USB-C power brick,
• A user manual

The cables are only a meter long, so take that into consideration when deciding if you need to purchase a longer set of cables. The inclusion of a power brick is commendable never skimps on it.

How Is the Design and Ergonomics?

The UColor O2 reminds me of an oversized iPad, while actually being thinner than the 2020 iPad Air. As such, it blends in nicely when placed next to modern laptops as a secondary display. The build quality is excellent, too. Thanks to the rigidity of the aluminum case, the panel doesn't flex when handled, nor does it creak or raise any concerns in the context of daily on-the-go use.

Around the back there are also four mounting holes compatible with any stand or arm that supports standard VESA 75x75 hole spacing. The accompanying screws are supplied in the box.

The supplied foldable cover doubles as a stand, with a leather-like texture and inner grooves to prop up the monitor. One side attaches magnetically to the back, while the other folds over the front. Since it’s held in place only by friction, some care is needed when packing, it can slide off and leave the screen partially exposed.

The crevices on the inner side of the cover allow the panel to tilt at two angles—roughly 15° and 30°. I typically used the 15° tilt when placing the monitor beside my laptop or as a primary display, often tucking the cover under my keyboard to bring the screen closer for a more comfortable setup. The 30° angle is useful when positioning the UColor O2 below a desktop monitor, serving well as a secondary screen for toolbars or background apps.

How Portable Is the Monitor?

Measuring 354 × 242 × 6.5 mm and weighing just 720 grams, the UColor O2 slips easily into a standard laptop backpack. With a slim laptop, you can likely store both in the same compartment. Portability is clearly one of this monitor’s key strengths.

What Connectivity Options Are Available?

The UColor O2 offers two USB-C ports with DisplayPort Alt Mode and a Mini-HDMI port. Both USB-C ports function identically, you can use either for video or power. USB-C supports the full 2880×1800 resolution at 120 Hz, while HDMI limits you to 100 Hz at native resolution. Attempting 120 Hz over HDMI causes Windows to quietly drop the resolution to 2560×1600, reducing sharpness and screen space.

Like many USB-C monitors, the UColor O2 can run on a single cable for both power and video. However, this limits peak brightness. If the monitor draws more power than your device can supply, it may shut off briefly and reset brightness to 15 (about 70 cd/m²). When connected to a Lenovo ThinkBook 16 G7 via USB-C, I reached brightness level 60 (253 cd/m²) at 120 Hz and full resolution, impressive performance for portable use, even in bright rooms.

Using the included power brick unlocks full brightness, though the monitor doesn't support USB PD passthrough, so it won't charge your laptop. It can charge your phone at around 7 W, which is fine for basic USB-C power without PD negotiation.

What Is the Power Consumption?

The UColor O2 comes with a 30 W USB-C power adapter. Using the Meross MSS315 Matter Smart Wi-Fi Plug and its app, I measured power consumption at different brightness levels and in Power Saving mode, which activates when the PC goes to sleep.

The results confirm the UColor O2’s efficiency as a portable monitor. Power draw stays well below the 30 W limit, allowing it to reach 250 cd/m² brightness through a single USB-C connection without overloading the laptop or significantly draining its battery.

How Are the Controls and On-Screen Display (OSD)?

The UColor O2 uses the same hard plastic buttons as the UMax 21.5 for OSD navigation, but they're spaced further apart and are therefore significantly more intuitive to use.

The bottom three buttons provide quick access to key settings: input selection, brightness, and speaker volume.

To access the OSD, press the second button from the top, then navigate through six menus: Brightness, Image, Color Temp., OSD Setting, Reset, and Misc. Most adjustments happen in the Brightness and Color Temp. menus, where you can fine-tune brightness and color temperature to optimize panel performance.

How Is the Overall Picture Quality?

The UColor O2 packs a 16-inch OLED screen with a 2880x1800 resolution, giving you a 16:10 aspect ratio that’s more productive than the usual 16:9. With a pixel density of 212.26 PPI, it’s sharp, no fringing, no issues with text or graphics. The image quality here is excellent, and the high pixel density makes it a pleasure to look at.

Windows suggests using 200% scaling, which is great if you have eyesight issues. But I’d recommend trying 150%, if you can manage it, you'll get a lot more screen space. Personally, I stuck with 150% after trying both.

Being OLED, the UColor O2 doesn’t rely on a backlight. Each pixel is self-emitting, giving you perfect blacks, infinite contrast, and a lightning-fast response time.

The screen is glossy, which boosts color vibrancy and contrast. But it also means reflections are more noticeable, especially in brighter environments or when displaying dark content, something to keep in mind for a portable monitor.

The rounded corners of the screen don’t interfere with Windows, everything displays as it should, with no cut-off content or issues with the cursor.

How Does the Picture Quality Perform at Factory Settings?

To evaluate picture quality, I tested the UPERFECT UColor O2 using an X-Rite i1Display Pro with DisplayCAL and Calman after a one-hour warm-up using the supplied 30 W power adapter.

Factory performance in the sRGB color space is generally decent, though not ideal for color-critical work. As expected for an OLED panel, contrast and black levels are stellar. The UColor O2 covers 146.6% of the sRGB gamut, which gives images a vibrant, punchy look, great for media, but overly saturated for standard sRGB workflows like web content. Unfortunately, there's no sRGB clamp in the OSD to correct this.

Color accuracy reflects that oversaturation, with an average ∆E of 4.15 and a peak of 7.73, especially in skin tones and blues. Grayscale fares better, with an average ∆E of 2.3, sufficient for daily use. The panel leans cool due to a blue push in midtones and highlights, with a measured color temperature of around 6,985 K. Gamma tracks at 2.29, producing slightly deeper shadows, but nothing concerning for regular SDR content.

When measured in the DCI-P3 color space, the UColor O2 shows what it's really capable of. Gamut coverage hits a full 100%, confirming the use of a true wide-gamut OLED panel. The CIE diagram shows accurate alignment of primary red, green, and blue coordinates, indicating solid factory tuning.

Color accuracy is much improved compared to sRGB measurements, with an average ∆E of 1.75 and a maximum of 3.12, well within acceptable limits for uncalibrated displays. A few tones, like darker skin and deep reds, show mild oversaturation or hue shift, but none exceed the critical ∆E of 5. Most colors fall within a ∆E of 2, delivering a natural and well-balanced image overall. It’s clear that UPERFECT has applied a decent factory profile targeting DCI-P3, reducing the need for calibration.

That said, I wanted to see if the image could be refined further by adjusting the color temperature toward the ideal 6,500 K. While unnecessary for most users, a few tweaks in the OSD brought the white point closer to target and set brightness to a comfortable 250 cd/m²—demonstrating that the panel has room for even more precision, if you're willing to fine-tune it.

Let's compare the measurements before and after doing the aforementioned OSD tweaks. The numbers shown in the table below are from measuring the panel in the sRGB color space, as these will be more relevant to the majority of users.

After manually adjusting the RGB gains in the OSD, the UColor O2 showed notable improvements in grayscale performance within the sRGB space. The average grayscale ∆E dropped from 2.3 to just 1, with a better RGB balance and a more accurate color temperature near 6,500 K. Gamma tracking stayed close to the 2.2 target, only rising slightly above 2.4 at full white, making near-whites appear a bit dimmer, but not problematic.

However, color accuracy in the sRGB space remains mediocre due to oversaturation, an expected result from a wide-gamut panel tuned for DCI-P3. Without an sRGB mode in the OSD, hardware calibration is the only way to achieve proper sRGB fidelity. That said, the UColor O2 still delivers sharp, vibrant visuals and is a solid choice for everyday use, as long as color-critical sRGB work isn’t your priority.

As expected from an OLED panel, the overall luminance, color and contrast uniformity is excellent. Out of 25 measured zones, none of them go over the 6% average luminance deviation, when compared to the referent (center) value. As such, the entire panel looks uniformly lit to the naked eye. Some slight color shifts, measured along the left edge, are visually subtle and essentially imperceptible. With that in mind, the uniformity performance of the UColor O2 is better than expected from a portable OLED panel.

How Does It Perform with HDR Content?

While OLED technology is typically well-suited for HDR content, the UColor O2 falls short in this area. Its peak brightness tops out at just 320 cd/m² (1% white window), and HDR support is poorly implemented.

Enabling HDR in Windows doesn’t trigger HDR mode automatically, you’ll need to dig into the “Reset” menu in the OSD and switch “HDR MODE” from Off to Auto. Even then, the image appears heavily tinted unless you manually tweak RGB gains (Red 49 / Green 50 / Blue 51 works decently). But expecting users to redo color settings every time they switch modes is impractical.

Worse, switching back to SDR doesn’t restore your previous settings, brightness stays locked until you disable HDR again in the same menu. Overall, the HDR mode is more frustrating than useful.

Thankfully, SDR performance is strong, and few people expect a 16-inch portable display to deliver a premium HDR experience. Still, this is a definite weak point worth keeping in mind.

What Are the Viewing Angles Like?

The viewing angles of the OLED panel built into the UColor O2 are excellent. There's no visible shift in colors from any sitting position or when changing positions.

How Well Does It Perform for Gaming?

The UColor O2 sports a 120 Hz refresh rate OLED panel with no adaptive synchronization support. At native resolution, the panel can reach 120 Hz refresh rate only when USB-C input is used. HDMI connectivity is capped at 100 Hz, unless you're willing to use a lower resolution.

What Is the Response Time and Overdrive Performance?

Using the OSRTT Pro (Open Source Response Time Tool), developed by Andrew McDonald of TechTeamGB, I tested the UColor O2’s pixel response at 120 Hz. The tool, along with the OSRTT Launcher app, provides detailed heatmaps and metrics.

Learn more in the technical documentation or visit the official website.

Here are the three key metrics OSRTT provides:

• Perceived Response Time
  • Measures the full transition time between colors, including overshoot recovery.
  • The UColor O2 delivered an average of just 0.9 ms, offering smooth motion with almost no blur.
• RGB Overshoot
  • Indicates how much a pixel goes beyond its target value during a transition.
  • Minimal overshoot was observed, with no visible haloing even without overdrive settings.
• Visual Response Rating (VRR)
  • A calculated score: 100 – (Initial Response Time + Perceived Response Time) .
  • Rewards fast, accurate transitions. The UColor O2 scores very well in this regard.

With sub-1 ms response times and clean motion handling, the UColor O2 performs impressively in fast-moving content. It's more than capable for video, casual gaming, and everyday use, even without any overdrive control.

How Much Input Lag Does It Have? 

To measure input lag, I used the OSRTT Pro Tool instead of LDAT V2. Thanks to its DirectX-based approach, it isolates monitor latency from external variables like USB polling and game render time, providing more accurate results.

After 100 test runs, the UColor O2 recorded:

• Average Input Lag: Around 9 ms at 120 Hz
  This is relatively high for a 120 Hz OLED panel and falls behind what’s typically expected from gaming-oriented displays.
• Practical Impact:
  • For general use, media, and casual gaming, the delay is negligible.
  • For competitive or latency-sensitive gaming, the lag is noticeable and places the UColor O2 behind faster desktop OLEDs and portable IPS options.

Value and Conclusion

The UColor O2 gets the essentials right for a portable OLED monitor. While not without flaws, it delivers a sharp, vibrant image in a slim and travel-friendly package.

What it does well:

• Sharp 3K OLED panel (2880×1800, 212 PPI) with 16:10 aspect ratio—great for productivity
• Excellent contrast and black levels, as expected from OLED
• 100% DCI-P3 gamut coverage with decent factory tuning
• Fast pixel response times and smooth 120 Hz refresh rate over USB-C
• Very low power consumption, enabling single-cable setups
• Sturdy metal build, lightweight at 720 g
• All key accessories included, including a 30 W charger and magnetic stand cover

Where it falls short:

• No sRGB clamp, leading to oversaturation in color-managed workflows
• HDR mode is poorly implemented and difficult to use
• Glossy screen causes reflections in bright environments
• Input lag (~9 ms) is higher than expected for a 120 Hz OLED
• No USB PD passthrough, so it won’t charge your laptop

Verdict:
At $350 (or $300 with code TPU50), the UColor O2 is a compelling choice if you want a high-resolution OLED with vibrant visuals and excellent portability. Just don’t count on it for color-accurate sRGB work or serious HDR use.