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If you want a clean, no-fuss two-in-one adapter that splits your USB-C port into charging plus a classic 3.5mm headphone jack, choose Vcddom USB C; if you need a three-way splitter that also gives you a USB-C headphone port for modern wired earbuds, choose caojunzhen 1.
• Vcddom USB C — biggest strength: a straightforward 2-in-1 split (60W PD charging + 3.5mm aux) with a 24bit/96kHz DAC, in a compact white dongle that's easy to pocket.
• Vcddom USB C — biggest trade-off: no data transfer, no USB-C headphone output, and it explicitly does not work with Moto or OnePlus phones.
• caojunzhen 1 — biggest strength: a 3-way split (60W PD charging + 3.5mm jack + USB-C headphone jack) with a 16bit/192kHz or 24bit/96kHz DAC and 16bit/48kHz ADC, so both old and new wired headphones work.
• caojunzhen 1 — biggest trade-off: no data transfer, it ships in red only, and the wider port layout adds a bit more bulk to carry.
• Who each pick is for: go Vcddom if you just want to charge and plug in a standard 3.5mm headset; go caojunzhen if you own USB-C headphones and don't want to give up charging or your old 3.5mm pair.
The Vcddom USB C is a 2-in-1 adapter, and it's honest about what that means. One end plugs into your phone, tablet or laptop's USB-C port; the other end splits into a PD-compatible USB-C charging port and a 3.5mm audio jack. That's it — two jobs, done cleanly. The charging side supports 60W PD3.0, and Vcddom notes a built-in chip that reads the voltage and current your device wants and holds them steady, which matters if you're charging a power-hungry tablet or laptop. The audio side runs a DAC rated at 24bit/96kHz stereo and supports both CTIA and OMTP 3.5mm headphone standards, so most older wired headsets should behave.
In my opinion, this is the pick for someone who lives with a 3.5mm pair of wired headphones — the ones with the round plug — and simply wants to keep using them while charging. Students, commuters, and anyone taking calls on a wired headset fit here. The compatibility list is broad: iPhone 15 through 17, most recent Galaxy S and Note models, Google Pixel 5 through 10, iPads, and MacBooks. It's also small — roughly 3.9 by 1.6 by 0.8 inches — so it disappears into a bag pocket.
Who should skip it? Two groups. First, anyone with USB-C headphones: there's no USB-C audio port here, only the 3.5mm jack. Second, Moto and OnePlus owners — Vcddom states plainly that this adapter is not compatible with those phones. If either applies to you, keep reading, because the other option solves exactly those problems.
The caojunzhen 1 takes the same idea and adds a third branch. Plug it into your USB-C port and you get a PD-compatible USB-C charging port, a 3.5mm audio jack, and a USB-C headphone jack. That third port is the whole reason this adapter exists. If you've bought a pair of USB-C wired earbuds — increasingly common now that headphone jacks are disappearing — this lets you use them and keep charging, or use them alongside a friend's 3.5mm set.
The audio specs are a touch more detailed on paper: the DAC handles 16bit/192kHz or 24bit/96kHz, and there's a 16bit/48kHz ADC on the input side. The listing also claims it avoids current noise, which is the low hum some cheap adapters introduce. Charging matches the Vcddom at 60W PD with the same built-in chip approach and the same advice to pair it with a PD wall charger. Compatibility covers iPhone 15/16, Pixel 7/8, and a long list of Galaxy S and Note models, plus laptops, tablets and PCs.
This is the adapter for the person who refuses to choose between old and new headphones — or who shares a device between a 3.5mm set at home and USB-C buds on the go. The trade-offs are real, though: it only comes in red, it's a three-port splitter so it's a slightly bulkier thing to carry, no data transfer is supported, and there's no explicit Moto/OnePlus exclusion warning, but I wouldn't assume it fixes that either. If you never touch USB-C headphones, that third port is dead weight you're paying for.
• Best for USB-C headphones → caojunzhen 1. It's the only one of the two with a dedicated USB-C audio port.
• Best for 3.5mm-only users → Vcddom USB C. You get the jack and charging without paying for a port you'll never use.
• Best for audio spec headroom → caojunzhen 1. Its DAC covers 16bit/192kHz as well as 24bit/96kHz, and it adds a 16bit/48kHz ADC.
• Best for low-noise wired listening → caojunzhen 1, based on its stated noise-avoidance design (Vcddom doesn't make that specific claim).
• Best for a minimal, pocketable dongle → Vcddom USB C. Two ports, one small white body.
• Best for color choice → Vcddom USB C. It's offered in white; caojunzhen is red only, per the listing.
• Best for iPhone 17 / Pixel 9–10 owners → Vcddom USB C, since its compatibility list names those newer models explicitly.
• Best for Moto or OnePlus owners → neither, unfortunately. Vcddom rules those phones out, and caojunzhen makes no such guarantee.
• Best for charging speed → a tie. Both are rated 60W PD3.0 with the same PD-charger recommendation. Neither supports data transfer.
If I had to pick one, I'd buy the caojunzhen 1 — but only because of the USB-C headphone port. That third jack future-proofs the adapter: as more wired earbuds move to USB-C, you won't need to buy a second dongle, and you still keep the 3.5mm jack for older gear. The slightly richer DAC/ADC spec doesn't hurt either. If you know you'll only ever use a round-plug headset and want the smallest possible thing in your pocket, the Vcddom USB C is the smarter buy. Either way, check the current price on Amazon before deciding — both are inexpensive accessories, and the gap may be smaller than you expect.
No. Vcddom splits into two ports (charging + 3.5mm), while caojunzhen splits into three (charging + 3.5mm + USB-C headphones). The extra USB-C audio port is the key difference.
No. Both listings explicitly state data transmission is not supported. They're for charging and audio only — don't expect to move files through them.
On paper, caojunzhen's DAC covers a wider range (16bit/192kHz and 24bit/96kHz) and adds a 16bit/48kHz ADC, while Vcddom specifies 24bit/96kHz stereo. Both are Hi-Fi-class for everyday listening; caojunzhen simply lists more.
No. Vcddom states the adapter is not compatible with Moto or OnePlus phones. caojunzhen's listing doesn't claim support for those brands either, so I'd treat both as a no-go for those devices.
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