How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want an all-in-one set of open-ear earbuds you can wear straight out of the box, choose Monster Earbuds Open AC601; if you need a rugged protective case for your Shokz OpenFit 2+ charging case, choose PROfezzion Shokz OpenFit 2+.
• Monster Earbuds Open AC601 — biggest strength: A complete open-ear earbud package with 13mm dynamic drivers, Bluetooth 5.4, ENC call noise reduction, touch controls, IPX5 water resistance, and up to 32 hours of total battery life with the charging case.
• Monster Earbuds Open AC601 — biggest trade-off: The clip-on, open-ear design leaks sound by nature and won't isolate you from loud environments the way in-ear buds do.
• PROfezzion Shokz OpenFit 2+ — biggest strength: A heavy-duty hard-shell case cover with a locking latch, IPX5 water resistance, and a non-slip silicone pad that grips the charging case firmly.
• PROfezzion Shokz OpenFit 2+ — biggest trade-off: It is a case cover only — it does not include headphones and works exclusively with the Shokz OpenFit 2+ (2025).
• Who each pick is for: Monster AC601 is for someone who wants actual earbuds for workouts, commutes, and calls; PROfezzion is for an existing Shokz OpenFit 2+ owner who wants to protect their charging case.
The AC601 is a self-contained pair of open-ear earbuds. Monster builds it around a 13mm PVK composite sound film driver with a 20Hz–20,000Hz frequency range, so you're getting a full-range dynamic driver in a clip-on, open-ear form factor. The design is plastic and silicone, light purple, and shaped as a bud that rests over the ear rather than inside it. That open placement is the whole point: you keep your ear canal clear, you stay aware of traffic, gym noise, or a coworker calling your name, and you don't get that plugged-up feeling after an hour of listening.
For everyday use, the feature list reads like a commuter-and-gym tool. Bluetooth 5.4 handles the connection, and Monster claims synchronized audio-video playback with low latency for gaming or calls. Environmental Noise Cancellation works on the microphone side — it's there to make your voice clearer on calls, not to block the world out. Touch controls cover answer, track skip, and volume, so your phone can stay in your pocket. And the IPX5 rating means rain and heavy sweat are accounted for, which is exactly the scenario open-ear buds tend to get used in. Battery is listed at a 32-hour total with the charging case, which is a genuinely long runway between charges.
Who should buy it: anyone who wants one product that does the whole job — listening, calls, workouts, and outdoor sessions — without buying headphones and a case separately. Who should skip it: if you need serious noise isolation for flights or a loud open-plan office, or if you already own a Shokz OpenFit 2+ and only want to protect your case, this isn't the product for that job.
PROfezzion Shokz OpenFit 2+: Who It's For
What it does, it does with intent. The shell is built from ABS, polycarbonate, metal, plastic, and silicone, with a drop-proof design and full-coverage protection against splashes and spills at an IPX5 water-resistance rating — the same water-resistance tier as the Monster buds, but applied to a case rather than an earbud. The secure locking latch is the standout detail: it holds the charging case shut so your earbuds don't pop out if the case takes a tumble. Inside, a non-slip silicone pad at the bottom grips the charging case so it doesn't rattle around — and unlike covers that rely on adhesive tape, there's nothing sticky to degrade over time. It's lightweight at 0.08 kg, measures roughly 3.01 x 2.81 x 1.33 inches, and carries a 1-year warranty.
Who should buy it: a Shokz OpenFit 2+ owner who tosses their case in a bag or backpack and wants it to survive drops, dust, and rain. Who should skip it: anyone who doesn't own the OpenFit 2+ (2025), and anyone shopping for actual earbuds — this adds zero audio capability.
• Best for actually listening to music → Monster Earbuds Open AC601. It has drivers, Bluetooth, and controls; the PROfezzion is a shell.
• Best for battery life → Monster Earbuds Open AC601. Up to 32 hours total with the charging case, versus no battery at all in a case cover.
• Best for call clarity → Monster Earbuds Open AC601. ENC technology targets background noise on your voice during calls.
• Best for protecting an OpenFit 2+ charging case → PROfezzion Shokz OpenFit 2+. Full coverage, a locking latch, and a drop-proof hard shell.
• Best for workouts and rain → Monster Earbuds Open AC601 for the buds themselves; PROfezzion if you want the case to shrug off splashes too. Both are rated IPX5, but they protect different things.
• Best for low-latency gaming and video → Monster Earbuds Open AC601. Bluetooth 5.4 with synchronized audio-video playback.
• Best for people who already own Shokz OpenFit 2+ → PROfezzion Shokz OpenFit 2+. It's the only one of the two that's relevant to you.
• Best for a single purchase that covers everything → Monster Earbuds Open AC601. The PROfezzion is an add-on, not a replacement.
My Verdict
are headphones waterproof
Not in the strict sense — "waterproof" usually means sealed against immersion, which neither product claims. The Monster Earbuds Open AC601 carries an IPX5 rating, which means it resists water splashes, spills, and heavy perspiration. The PROfezzion Shokz OpenFit 2+ case cover is also rated IPX5. Both handle rain and sweat, not swimming.
are headphones water resistant
Yes — that's exactly what IPX5 describes. IPX5 means protection against water projected from a nozzle, so splashes, spills, and sweat are covered. The Monster AC601 uses IPX5 for the earbuds themselves, while the PROfezzion case cover uses IPX5 to protect your OpenFit 2+ charging case. Neither is rated for full submersion.
No. It's a heavy-duty hard-shell case cover for the Shokz OpenFit 2+ (2025) charging case. It includes no drivers, no Bluetooth, and no battery. If you're looking for earbuds, the Monster Earbuds Open AC601 is the actual headphone in this comparison.
No. PROfezzion states it is only compatible with the Shokz OpenFit 2+ (2025), and not with the OpenFit Air (2024) or the original OpenFit 1 (2023). Check your exact model before ordering, because the fit is specific to the OpenFit 2+.
As an Amazon Associate I earn from qualifying purchases.
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.
When you buy through links on this page, we may earn a commission from qualifying purchases at no extra cost to you.
Amazon and the Amazon logo are trademarks of Amazon or its affiliates. This site is an independent third-party review and is not affiliated with, endorsed by, or sponsored by Amazon or the product brands mentioned.
See also: Monster Open Ear AC210 vs PROfezzion Shokz OpenFit 2+, Ugreen USB-C vs Monster Open Ear AC322, HIFI WALKER Open Ear Earbuds vs EKSA H27: Over Ear Office