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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-09-20 · 8 min read · Independent comparison
• ZOpid Earbuds — biggest strength: up to 30 hours of total playtime plus 100 hours of standby, with a charging case that holds a 480 mAh battery and earbuds rated at 8–10 hours of working time per charge (double ear).
• ZOpid Earbuds — biggest trade-off: it's an in-ear, ear-hook design on Bluetooth 5.0 + EDR, so it physically plugs your ear canal and uses an older wireless standard.
• Monster Earbuds Open AC601 — biggest strength: open-ear clip-on comfort with Bluetooth 5.4, 13 mm drivers and ENC noise reduction for calls, in a light 0.15 kg package.
• Monster Earbuds Open AC601 — biggest trade-off: 32 hours total playtime is only slightly ahead on paper, and the open-ear shape means no in-ear isolation from your surroundings.
• Pick ZOpid Earbuds if you want an in-ear sports fit for running and gym work, long standby between charges, and a case that can be charged wirelessly.
• Pick Monster Earbuds Open AC601 if you want to hear your environment, take calls in noisy places, and wear earbuds for hours without pressure inside your ears.
The ZOpid Earbuds are a classic true-wireless in-ear sport set. The design is ear hooks with rounded tips, so the buds anchor around the outside of your ear and push a tip into the canal. That's a fit built for movement: running, lifting, rowing, any session where a bud popping out is the enemy. The ear hooks are described as soft and adjustable, and the package includes small and large earplugs on top of the medium ones installed at the factory, so you can tune the seal rather than accept whatever comes in the box.
On the spec sheet, the numbers that matter most are battery and range. Each earbud carries an 80 mAh battery, the case carries 480 mAh, and ZOpid rates the result at up to 30 hours of total playtime and 100 hours of standby. Working time is listed at 8–10 hours per charge with both buds in use, and talk time at 10–12 hours. Charging takes about 2 hours. Bluetooth is version 5.0 + EDR across the HFP, HSP, A2DP and AVRCP profiles, running on a JL AC6936 chipset, with a stated range up to 30 feet line of sight. The frequency range is the standard 20 Hz – 20,000 Hz with a dynamic driver, and ZOpid advertises HD sound with deep bass.
A few practical touches stand out. You can use one bud or both — the set switches between stereo and mono — and everything runs off a single button rather than touch gestures, which is genuinely easier with sweaty or gloved hands. The case has a fabric cover and an LED indicator, and the listing calls it a wireless charging case. IPX5 means it shrugs off sweat and splashes, not full submersion. ZOpid also covers it with a one-year parts and labor warranty.
Who should buy it: runners, gym regulars and anyone who wants an in-ear seal, a hooked fit that stays put, and a long standby so the buds are ready when you grab them after a week in a bag. It's also a sensible pick if you take long calls and want mono mode plus a physical button.
Who should skip it: if you hate the feeling of tips inside your ear canal, want to hear traffic while cycling, or want the newest Bluetooth generation for low-latency gaming, this isn't the set for you. It's Bluetooth 5.0, and that's a real limitation next to the Monster's 5.4.
The Monster Earbuds Open AC601 are the opposite philosophy. These are open-ear clip-on buds: nothing enters your ear canal. Instead, a clip holds a small bud against the outside of your ear and fires sound toward it. The result is a much lighter, airier feeling — the whole product weighs 0.15 kg — and you stay aware of what's around you. For cyclists, runners on shared paths, and anyone working in an office who needs to hear a colleague walk up, that openness is the entire point.
The hardware is newer. Bluetooth 5.4 is the headline, and Monster specifically calls out low latency and synchronized audio-video playback, which matters if you game or watch video and hate lip-sync drift. The drivers are 13 mm dynamic units with a PVK composite sound film, covering 20 Hz – 20,000 Hz, and Monster markets the tuning as Hi-Fi with strong bass and clear highs. For calls, there's Environmental Noise Cancellation (ENC) aimed at the microphone side — it's about making your voice clear to the person on the other end, not about blocking noise for you.
Battery is rated at 32 hours total including the charging case, which is a touch more than ZOpid's 30, though Monster doesn't break out per-bud playtime the way ZOpid does. The enclosure is plastic and silicone, the color is light purple, and controls are touch-based: tap to answer calls, skip tracks and adjust volume. IPX5 gives you the same sweat-and-rain protection as the ZOpid. The clip-on design is meant to hold firm through vigorous activity, and the package is described as portable and secure.
Who should buy it: commuters, cyclists, walkers and office workers who want situational awareness, plus anyone who finds in-ear tips uncomfortable after an hour. If you take a lot of calls in busy places, the ENC and the newer Bluetooth stack are the draw.
Side-by-Side: Which Should You Choose?
• Best for total battery life → ZOpid Earbuds. Up to 30 hours total, 100 hours standby, with per-bud working time (8–10 hours) and talk time (10–12 hours) spelled out.
• Best for situational awareness → Monster Earbuds Open AC601. Open-ear clip-on design keeps your surroundings audible.
• Best for call clarity in noise → Monster Earbuds Open AC601. ENC targets the microphone so your voice cuts through background chatter.
• Best for secure in-ear fit during hard workouts → ZOpid Earbuds. Adjustable soft ear hooks plus three earplug sizes.
• Best for gaming and video → Monster Earbuds Open AC601. Bluetooth 5.4 with low latency and synchronized audio-video.
• Best for long standby between sessions → ZOpid Earbuds. 100 hours of standby means it's charged when you reach for it.
• Best for all-day comfort and light weight → Monster Earbuds Open AC601. 0.15 kg and no pressure inside the ear canal.
• Best for simple, glove-friendly controls → ZOpid Earbuds. One physical button, no touch guessing.
• Best for people who dislike in-ear tips → Monster Earbuds Open AC601. Nothing goes into your ear.
In my opinion, the ZOpid Earbuds are the better buy for anyone whose priority is a locked-in fit for running, gym work and long calls, backed by the most clearly documented battery figures here — 30 hours total, 100 hours standby, and a stated 8–10 hours per charge. The Monster Earbuds Open AC601 win on a different axis: if you want to stay aware of your surroundings, take clearer calls in noise, and get Bluetooth 5.4 with low-latency video sync in an open-ear shape, that's the set I'd recommend. I'd buy the ZOpid for training and the Monster for commuting and desk work. If you're stuck, ask which matters more — isolation or awareness — and the answer picks itself. Check the current price on Amazon before you commit, since pricing shifts and both sit in a similar budget tier.
FAQ
Both handle sweat with IPX5, so it comes down to fit. ZOpid's ear hooks and in-ear tips anchor the bud and isolate sound; the Monster's open clip-on stays aware of traffic and won't plug your canal. For treadmill and gym work I'd lean ZOpid; for outdoor running near roads, the Monster.
On paper they're close. ZOpid states up to 30 hours total with 100 hours standby, plus 8–10 hours working time and 10–12 hours talk time per charge. Monster states 32 hours total including the case but doesn't break out per-bud figures. ZOpid gives you more detail; Monster claims slightly more total.
The spec sheet lists active noise cancellation under noise control, and the in-ear tips physically block some outside sound as well. That's a very different approach from the Monster Open AC601, whose ENC is aimed at cleaning up your voice on calls rather than blocking noise for you.
I don't publish prices here because they change often and vary by seller. Both are positioned as budget-friendly wireless earbuds, so check the current price on Amazon using the button on this page before deciding.
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