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If you want one pair of earbuds that survives open-water laps, city-street cycling and long marathon training blocks, choose Opinta Swimming Headphones; if you need tiny in-ear buds that disappear in your ears for sleeping, working and side-sleeping comfort, choose Piegricdiat Invisible Sleep Headphones.
• Opinta Swimming Headphones — biggest strength: IPX8 waterproofing plus a 32GB built-in memory card, so you can swim, cycle or run with no phone and no water anxiety. The trade-off: bone conduction sits outside your ear canal, so there is no noise isolation at all — you hear everything around you.
• Piegricdiat Invisible Sleep Headphones — biggest strength: a genuinely tiny in-ear design built around side sleepers, with skin-soft silicone tips and a sleep mode that disables the buttons so you don't trigger them while you roll over. The trade-off: IPX6, not IPX8, and Bluetooth 5.3 rather than the newer 6.0 standard on the Opinta.
• Best for swimming and multi-sport use → Opinta Swimming Headphones. It is the only one of the two that carries an IPX8 rating and a dedicated MP3 mode for underwater playback.
• Best for sleep and all-day wear → Piegricdiat Invisible Sleep Headphones. Side sleepers, shift workers and anyone who wants earbuds hidden at work will get more out of these.
• Best for phone-free workouts → Opinta Swimming Headphones, thanks to that 32GB card and support for MP3, WAV, WMA, M4A and FLAC.
The Opinta Swimming Headphones are, first and foremost, an open-ear bone conduction headset. That single design decision explains almost everything else about them. Because the drivers sit against your cheekbone instead of inside your ear canal, your ears stay completely open. On a bike, that matters. You keep your hearing for traffic, bells, car doors and other riders — the kind of awareness that in-ear buds actively take away from you.
The second thing that defines these is the IPX8 rating. IPX8 is the deepest water-resistance tier in this comparison, and Opinta pairs it with a practical instruction that tells you a lot: switch to MP3 mode when you go underwater, because Bluetooth signals don't travel through water. That is exactly why the 32GB of built-in memory exists. You load your tracks, leave your phone in your bag or at the poolside, and the headphones play on their own. Opinta says that's room for roughly 8,000 tracks, and the supported formats cover everything from MP3 to FLAC.
Battery and connectivity round out the picture. Bluetooth 6.0 with a 10-metre range, a 2-hour charge, up to 8 hours of playback and up to 110 hours of standby. Magnetic charging means no fiddly port to plug in. The built-in microphone handles calls and voice assistant commands, and the whole thing weighs just 0.11 kg. A one-year warranty is included, and the colour is orange.
Who should buy it? Cyclists who want to hear the road, swimmers who want music without a phone, and runners or marathon trainers who want one headset that covers every session in a week. Who should skip it? Anyone who wants to block out noise. There is no noise control here at all — that openness is the point, but it's a dealbreaker if you want silence on a plane or in a noisy office.
The Piegricdiat Invisible Sleep Headphones go in the opposite direction entirely. These are in-ear buds — beige, with a pink carrying case — and their whole reason for existing is comfort in situations where normal earbuds hurt. The proprietary skin-soft silicone eartips and eartip caps are designed so you can lie on your side through the night without pressure building up on your ear. If you've ever woken up with sore ears from ordinary buds, you know exactly what problem this solves.
The sleep mode is the clever bit. Once it's on, every button on the buds is disabled, so you can only control playback from your phone. That removes the single most annoying thing about sleeping in earbuds: accidentally pressing something when you turn over. Piegricdiat also claims the buds can be used underwater for more than 6 hours continuously, and the IPX6 rating supports swimming, surfing and snorkelling. Note that IPX6 is a lower water-resistance tier than the Opinta's IPX8 — fine for surface water sports, less bulletproof for repeated submersion.
Audio-wise you get Bluetooth 5.3 with a binaural chip, 3D surround sound and a whale-cavity stereo surround design that Piegricdiat says lifts the music experience. There's a built-in noise-reduction microphone for calls, plus passive noise cancellation — the seal of the tip does the blocking rather than active electronics. Charging takes 1 hour. The buds are sold as a single item with a user manual, and the age range is listed as all ages.
Who should buy it? Side sleepers, people who nap on commutes, night-shift workers, and anyone who wants earbuds so small they're effectively invisible at a desk. Who should skip it? Cyclists, mainly. In-ear buds with passive noise cancellation seal you off from traffic noise, and the Piegricdiat has no built-in memory — it needs a Bluetooth connection to a phone at all times.
Side-by-Side: Which Should You Choose?
• Best for swimming underwater → Opinta Swimming Headphones. IPX8 plus MP3 mode beats IPX6 with Bluetooth-only playback.
• Best for side sleeping → Piegricdiat Invisible Sleep Headphones. That's literally what they were designed for.
• Best for phone-free workouts → Opinta Swimming Headphones. 32GB of storage and no need to carry a handset.
• Best for blocking out noise → Piegricdiat Invisible Sleep Headphones. Passive noise cancellation versus none at all.
• Best for staying aware of your surroundings → Opinta Swimming Headphones. Open-ear design, by definition.
• Best for newer Bluetooth → Opinta Swimming Headphones. Bluetooth 6.0 against Bluetooth 5.3.
• Best for discreet, hidden wear → Piegricdiat Invisible Sleep Headphones. The tiny in-ear shape disappears in your ears.
For a cycling-earbuds buyer, I'd take the Opinta Swimming Headphones. In my opinion, the combination of IPX8, Bluetooth 6.0, 32GB of on-board music and an open-ear fit that lets you hear the road is the more useful package for anyone riding regularly — and it happens to double as a swimming and marathon headset. The Piegricdiat is genuinely excellent at one job, sleep comfort, and if that's your priority it wins outright. But for cycling, I recommend the Opinta.
Yes — in my opinion they're the better of these two for cycling. The open-ear bone conduction design keeps your ears free to hear traffic, and Bluetooth 6.0 with a 10-metre range holds a stable connection on busy streets.
Can you swim with Piegricdiat Invisible Sleep Headphones?
Piegricdiat rates them IPX6 and says they support swimming, surfing and snorkelling, with underwater use quoted at more than 6 hours. That's a lower water-resistance tier than the Opinta's IPX8, so treat them as surface-water sport buds rather than dive-proof ones.
With the Opinta, no — the 32GB memory card plays stored music on its own, which is essential underwater since Bluetooth can't transmit there. The Piegricdiat relies on a Bluetooth 5.3 connection, so you'll want your phone nearby.
I can't quote prices here, and both listings change over time. Check the current price on Amazon using the button on this page before you decide — the right pick depends more on whether you ride or sleep in them than on the number.
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