Overview
Yocan makes two of the most popular 510 box mods on the market right now, and they're priced just $5 apart. The UNI Pro 2.0 runs $34.99. The UNI 3.0 costs $40. Both use 650mAh batteries, both fit any cartridge, and both have digital displays with variable voltage.
So what's the actual difference? More than you'd think.
The Pro 2.0 is the practical pick. Metal body, OLED screen you can read in sunlight, and 0.1V precision voltage control. The UNI 3.0 is the flashier option. Bigger animated display, wider voltage range down to 1.8V, and a dozen color choices including some wild spatter editions.
The UNI Pro 2.0 has been around since January 2022 (per Yocan's Shopify listing). The UNI 3.0 is much newer, listed in December 2024. So the 3.0 is Yocan's latest take on the UNI formula, while the Pro 2.0 is the more established, battle-tested option.
We tested both side by side across multiple cartridges and daily sessions. Here's how they compare in the areas that actually matter.
Build and Design
This is where the two devices feel most different in your hand.
The UNI Pro 2.0 uses a zinc alloy metal body. It's noticeably heavier than the UNI 3.0 and has a solid, premium feel that inspires confidence. It doesn't creak, it resists scratches well, and it looks clean after weeks of pocket carry. At 69mm x 44mm x 22mm, it's also slightly more compact.
The UNI 3.0 uses a plastic ABS body. It's lighter, which some people prefer, but it doesn't feel as durable or expensive. The tradeoff is that Yocan went wild with color options: 12+ choices including standard solids and spatter editions (Black-Red, Purple-Black, Teal-Black) that look genuinely cool. The spatter colors run $50, though.
Both devices share the same adjustable cartridge chamber with the width dial and height mechanism. Both hide your cart inside the body for a discreet look. Both have an oil viewing window.
The Pro 2.0 has a clear edge here. Metal beats plastic for everyday durability, and the $5 savings just widens the gap. The UNI 3.0 counters with better aesthetics if you care about color variety, plus it has a lanyard hole that the Pro 2.0 lacks.
Display Comparison
Two very different approaches to showing you information.
The Pro 2.0 has an OLED screen. It's small, crisp, and bright. You get your voltage, puff count, and battery level in a clean layout. Nothing fancy, but it does the job well. The biggest perk: it's easy to read outside. Direct sunlight doesn't wash it out.
The UNI 3.0's display is larger and more animated. It shows voltage, battery, puff count, and ohms reading (the Pro 2.0 doesn't show resistance). You can pick from 3 animated backgrounds: Classic, Planet, and Shiny Cat. Some people love the personality. Others find it unnecessary.
The practical downside of the UNI 3.0's screen is visibility. In bright conditions, it gets significantly harder to read compared to the Pro 2.0's OLED. If you're someone who vapes outdoors often, this is worth considering. Indoors, both are perfectly fine.
The UNI 3.0 wins on information (it shows ohms) and style (animated themes). The Pro 2.0 wins on readability, which is arguably the whole point of having a screen.
Voltage Control
Here's where the decision gets interesting.
| Feature | UNI Pro 2.0 | UNI 3.0 |
|---|---|---|
| Voltage Range | 2.0V - 4.2V | 1.8V - 4.2V |
| Increment | 0.1V steps | Adjustable |
| Total Settings | 22 | Variable |
| Preheat | 10 seconds | Yes |
The Pro 2.0 gives you 0.1V precision across 22 settings from 2.0V to 4.2V. That's granular control. You can dial in 2.7V versus 2.8V and test the difference.
The UNI 3.0 starts lower at 1.8V and goes to the same 4.2V ceiling. That extra 0.2V at the bottom doesn't sound like much, but 1.8V is genuinely useful for thin oils where you want pure flavor with minimal heat. It's the kind of setting you try once with a good live resin cart and then never go back from.
Here's the honest truth: most cart users find a voltage they like and leave it there. If you're a set-it-and-forget-it person who vapes around 2.5V to 3.2V, both devices cover that range equally well. The Pro 2.0's 0.1V precision is nice for dialing in, but once you've found your spot, it doesn't matter much day to day.
The 1.8V floor on the UNI 3.0, though, gives you access to a range the Pro 2.0 simply can't reach. If low-temp flavor chasing is your thing, that matters.
Full Spec Comparison
| Spec | UNI Pro 2.0 | UNI 3.0 |
|---|---|---|
| Price | $34.99 | $40.00 |
| Battery | 650mAh | 650mAh |
| Voltage Range | 2.0V - 4.2V | 1.8V - 4.2V |
| Voltage Steps | 0.1V increments | Adjustable |
| Display | OLED | Digital animated |
| Body Material | Zinc alloy (metal) | Plastic/ABS |
| Charging | USB-C | USB-C |
| Threading | 510 (magnetic adapter) | 510 |
| Preheat | 10 seconds | Yes |
| Puff Counter | Yes | Yes |
| Ohms Reader | No | Yes |
| Cart Adjustment | Width + height | Width + height |
| Oil Window | Yes | Yes |
| Lanyard Hole | No | Yes |
| Color Options | Limited | 12+ including spatter |
| Dimensions | 69 x 44 x 22mm | Slightly larger |
Performance
Both devices perform well, and the real-world differences are smaller than the spec sheet suggests.
Vapor production is consistent across both at the same voltage settings. Same battery capacity means similar battery life, roughly a full day for moderate users, and daily charging for heavier sessions. Both use USB-C, so charging is quick either way.
The magnetic 510 adapter that both devices use can occasionally be finicky. It's the most common complaint across the UNI lineup. Sometimes you need to adjust the adapter or clean the contacts to get a reliable connection. This isn't a dealbreaker, and it affects both equally, but it's worth knowing about.
Cart compatibility is identical. The adjustable width dial and height mechanism on both fit everything from slim half-gram carts to chunky full-gram ceramics. No complaints from either device across all the cartridges we tested.
If you need more battery life than 650mAh offers, both these devices might feel limiting for heavy all-day use. Check out the UNI Pro Plus if that's a concern.
Who Should Get the UNI Pro 2.0?
The Pro 2.0 is for people who want a reliable daily driver that feels solid in hand. You should pick this one if:
- Build quality matters to you. The metal body is genuinely nicer than plastic. It's the kind of thing that makes a $35 device feel like it costs more.
- You vape outdoors. The OLED screen stays readable in bright sunlight. This sounds minor until you're squinting at an animated cat trying to check your voltage.
- You want to save $5. Five dollars isn't life-changing, but when the cheaper option also has the better build, it's hard to argue against it.
- Precision voltage appeals to you. 22 voltage settings in 0.1V steps is about as fine-tuned as 510 batteries get at this price.
The Pro 2.0 is the best 510 box mod pick if you value substance over style.
Who Should Get the UNI 3.0?
The UNI 3.0 is for people who want a bit more range and personality. Go with this one if:
- You vape at very low voltages. The 1.8V floor is a real advantage for flavor-focused sessions with thin oils and live resin carts. That 0.2V below what the Pro 2.0 can do makes a noticeable difference.
- You want the ohms reader. Seeing your cartridge resistance can help you pick the right voltage, especially when trying new carts.
- Color and style matter. Twelve colors and animated display themes give the UNI 3.0 way more personality. The spatter editions are legitimately eye-catching (at a $10 premium).
- You want a lanyard option. If you prefer to wear your battery rather than pocket it, only the UNI 3.0 has that attachment hole.
The Bottom Line
You can't go wrong with either of these. Both are solid 510 box mods from Yocan with the same 650mAh battery, universal cart fit, and USB-C charging. They're closer in performance than their spec sheets suggest.
For most people, the UNI Pro 2.0 is the better buy. It costs less, it's built better, and the OLED screen just works without fuss. It does everything a cart battery should do, and the metal body makes it feel worth more than $35.
The UNI 3.0 earns its spot if you specifically want that 1.8V low end for flavor chasing or if the display themes and color options speak to you. It's a good device that costs a bit more for features that matter to some users and don't matter to others.
Pick the Pro 2.0 for the better tool. Pick the UNI 3.0 for the more fun toy. Either way, your carts are in good hands.
Considering a different kind of battery entirely? See how the UNI Pro 2.0 stacks up against the premium Vessel Compass in our other head-to-head comparison.