Tom's Guide Verdict
The Naenka Runner Diver are great bone conduction headphones, particularly for swimmers, offering good Bluetooth connectivity and 16GB music storage.
Enjoyable bone conduction sound
Has Bluetooth and 16GB storage playback mode
Easy to access physical controls
Not the slimmest bone conduction headphones
Shorter battery life in music player mode
Unsuitable for calls
Why you can trust Tom's Guide
Price: $149 / £119 / AU$223
Battery life (rated): 10 hours
Connectivity: Bluetooth 5.3
Durability: IPX8 waterproof
Weight: 1.23 ounces
The Naenka Runner Diver are bone conduction headphones that offer Bluetooth and music player streaming in one package, with a design that makes them suitable to use underwater.
The follow-up to Naenka’s Runner Pro offers more storage to pile your audio onto and a bigger battery to make sure you can use them longer in and out of the water.
They cost less than Shokz’ swim-friendly OpenSwim headphones, which only offer music player streaming, making the Runner Diver an attractive alternative for anyone looking for a good pair of waterproof bone conduction headphones.
Naenka Runner Diver review: Price and availability
The Naenka Runner Diver cost $149 / £119 / AU$223 putting them up against the Shokz OpenSwim ($149 / £169 / AU$239). There are cheaper waterproof bone conduction alternatives out there like the Creative Outlier Free Pro, which retails at $129 and you can currently pick up for closer to $100.
Naenka Runner Diver review: Design and comfort
The Runner Diver takes design inspiration from an interesting source, shaping its neckband headphones like a seahorse, which Naenka says makes the fit ideal for swimming.
Seahorse-inspired design aside, they're built from a mix of titanium and silicone to keep them light and also comfortable in key places where they sit against the head. They weigh 1.20 ounces (around 35g) and are bulkiest where the 16GB music player storage is kept, meaning they're not quite as slender as some bone conduction headphones out there.
The IPX8-rated design means they're suitable for being submerged in water up to 1.5 meters and Naenka states that they shouldn’t be used for longer than 40 minutes in the water at any one time.
There’s a set of physical buttons to adjust audio volume or skip through audio with a dedicated button also included to toggle Bluetooth streaming music player modes and turn the headphones on and off. There is a solitary microphone so you can take calls and speak to your smart assistant with microphone protection plugs included to cover up the mic when you enter the water with them.
In terms of fit and wearing them for extended periods, they’ve been absolutely fine during my tests. In the water they stay put, but it’s worth securing them under a swim cap for that extra sense of security. The controls are well positioned whether you’re using them stationary or on the move. They’re definitely not the slimmest and lightest bone conduction headphones out there, but they also haven’t been uncomfortable to wear in any sort of way either.
Naenka Runner Diver review: Sound and call quality
Whether you’re using the Runner Diver in Bluetooth streaming or music player mode, sound is delivered in the entirely same way using bone conduction technology. So it’ll keep your ears uncovered, transmitting sound up through transducers up the cheekbones and up towards the ears so you can hear whatever's playing as well as ambient noise around you at the same time.
The music player mode is primarily designed for underwater use and you’ll need to transfer audio files over to the headphones first by plugging it into a computer via USB port to drag and drop files onto it, which isn’t ideal for MacBook users like me. The Diver version I tested supports MP3 and FLAC files but there is an updated version that expands that support to M4A, WAV and APE files. Something you can’t do is load on music from streaming services, which definitely would’ve been a desirable feature.
Once you’ve made use of the 16GB storage and capacity for up to 2,400 songs, you’ve got the option to play audio in order with random play supported on the updated Runner Diver. I had to delve into the archives of my iTunes purchases and download some podcasts both music and conversation-based, to put the music player to good use.
That streaming mode both in and out of the water, was very good on the whole. Naenka also includes a set of earplugs to help better isolate sound during swimming use, but I found using the headphones without them still delivered largely enjoyable sound.
A lot of the music I had stored was dance and drum and bass tracks. The Runner Diver managed to handle that more bass-focused sound without letting it tear into the treble and mid frequency departments. I still enjoyed good detail and clarity when it was needed and that worked well when switching to more conversation-driven podcasts. It wasn’t as hollow or murky as I’d anticipated it would be during swims.
Out of the water and using either Bluetooth streaming or the music player you get something that’s versatile, offers good clarity and a welcome slight thud of bass. Listening to the Songs To Test Headphones playlist on Spotify (or even the Tom's Guide Headphone Demo playlist), I got a good reproduction of bass on tracks like Burial’s "Archangel", though at louder volumes that bass can send slightly more noticeable vibrations as the headphones work harder to deliver that more powerful sound. On Otis Redding’s "(Sittin’ On) the Dock of the Bay", the vocals sound pleasingly warm, and there’s enough detail in the treble department to make it a good match for podcasts and audiobooks.
If you want to make and take calls, I'd say the Runner Diver does an acceptable job but it’s not a pair of headphones to rely on for handling regular call time. I tested call quality indoors while working in a quiet room and outdoors with more environmental noise to contend with like wind and traffic. There’s just a single microphone here and introducing more noise does battle against what you can hear on calls and it can feel quiet and a touch hollow. It certainly performs better indoors in quieter environments.
Naenka Runner Diver review: Battery life
Naenka suggests you can expect up to 10 hours of battery life from the Runner Diver, which matches the promised battery life performance on the similarly priced Shokz OpenRun Pro. That 10 hours is possible when listening at 60% volume according to Naenka, so if you’re listening at higher volumes, the playback time will drop noticeably.
You can get 10 hours, but if you’re using the music player streaming, it’s going to be around half that as that onboard streaming clearly seems to demand more power from these bone conduction headphones.
When they do hit zero battery life, they take 1.5 hours to fully recharge again via the proprietary charging cable. Sadly, there's no fast charge mode to give you a quick top-up if you need to quickly use them when you’ve forgotten to charge them.
Naenka Runner Diver review: Verdict
The Naenka Runner Diver offers enjoyable bone conduction sound whether you’re swimming with them on or not, and delivers good battery life whether you’re using listening via Bluetooth or putting the onboard music player to good use.
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Michael is a freelance journalist who has covered consumer technology for over a decade and specializes in wearable and fitness tech. Previously editor of Wareable, he also co-ran the features and reviews sections of T3, and has a long list of bylines in the world of consumer tech sites.
With a focus on fitness trackers, headphones, running wearables, phones, and tablet, he has written for numerous publications including Wired UK, GQ, Men's Fitness, BBC Science Focus, Metro and Stuff, and has appeared on the BBC Travel Show. Michael is a keen swimmer, a runner with a number of marathons under his belt, and is also the co-founder of YouTube channel The Run Testers.