Nank(Naenka) Runner Diver2 Bone Conduction Swimming Headphones that Will Make You Sing Underwater

Nank(Naenka) formally known as Naenka are a Chinese manufacturer specialising in bone conduction headphones.

The Runner Diver 2 are its latest product. As well as Bluetooth (v5.3) support, there's 32GB of memory allowing for music files to be stored on the device itself.

The come in a box (that is remarkably similar dimensions to a competitor) which is mainly cardboard with some plastic inserts to hold various items such as the ear plugs, sound quality enhancers and the headphones themselves. They're also a USB-A charging cable and instruction manual.

Headphone box

If the USB cable is plugged into a PC (macOS or Windows), the headphones appear as a USB disk and music files which are MP3/M4A/WAV/APE/FLAC can be transferred. The headphones support multipoint paring (i.e. multiple devices).

Diver is probably not the best description for the headphones as they are only IP68 certified which is 1 metre depth in water for up to 30 minutes - so maybe Runner Swimmer would be more appropriate. While swimming it's necessary to use the MP3 mode as a Bluetooth connection may cut out when the headphones are submersed and will then try and reconnect as they come out of the water.

Looking under headphones

Bone conduction works by transferring the audio vibrations through the cheekbones so how the headphones fit is quite important. They comes with some silicon inserts called sound enhancers that fit into the ear itself, sitting on the indented bit before the ear canal (so not in the ear canal like in-ear earphones). The sound enhancers come in small, medium and large. The headphones then are placed over the ears.

Sound enhancers

The sound enhancers made a huge difference in sound quality and fit, however head shape has a lot to do with it and they may not make a huge difference for everyone. An obvious issue is that they sit in-front of the ear canal so do block some of the sounds from the environment which is why some people are using bone conduction headphones in the first place. There's good bass, midrange and treble supported by the 16 mm speaker. There's also built-in noise cancelling for the microphones.

looking form back

Battery life is 10 hours (at 60% volume) and 150 hours standby and a full charge takes 1.5 hours and 15 hours talk time. The magnetic connector is polarised so it will only fit one way, but the pins do protrude and can easily short onto any flat metallic material especially if it's ferrous as the magnets will be attracted to it.

Side view

The headphones are reasonably light weight at 32g and are covered in silicone that is skin friendly being soft, hypoallergenic and breathable. The design is meant to resemble a seahorse (well the bone conducting part).

Top view

There are 3 buttons, Power, "+" and "-".

Power button

Long Press 3 secs - Power On / Power Off

Double click - Wake up Voice assistant / exit voice assistant

Click Once - Play/Pause / Answer/Hangup

Double Click - Ignore call

Triple Click - Bluetooth/MP3 mode

Quad (4) clicks - Sequential/Random play in MP3 mode

+ Button

Click once - Volume Up

Long Press 2 seconds - Next song

- Button

Click once - Volume Down

Long Press 2 seconds - Last song

They retail for around £140.00 but a 15% discount is available using the code "Steve" (no quotes required).

As stated without the sound enhancers, the sound quality and fit wasn't brilliant and they vibrated against the skin annoyingly, with the sound enhanced things improved dramatically but that relates to head shape so things might be completely different for other users. With the sound enhancers sound quality was pretty good (as least as good as the competition). Not a bad headphone.

Kobo Aura ONE eReader

Kobo have been making eReaders for a while, but have never quite got the market penetration (compared to their book selling rival).

The Aura ONE is a nice unit. It's bigger than the competition (the screen is a 7.8 inch Carta E.ink display with a resolution of 1872 x 1404 at 300ppi). It weighs 226g. So it's about the same size as a paperback book and weighs about the same (195.1 x 138.5 x 6.9 mm). It charges via microUSB and battery life is up to a month (varying by usage of course). The display is backlit and it has a light sensor which will adjust the colour of the front light to suit ambient surroundings (and time of day, so it will reduce the blue content at night - which can potentially affect sleeping technology called ComfortLight PRO).

Several standard book formats are supported, including the most popular ePUP, ePUP3, PDF and MOBI. It can also display several image formats and comic book formats (CBZ and CBR).

The main new feature however is the water resistance, it can survive getting wet (IPX8 i.e. an hour in up to 2 meters of water). If reading in the bath is your fancy, this is the reader for you (or even in the shower, though that's less practical). It's probably usable on a beach too, though salt-water tends to mess things up really badly if it does get into the electronics.

When plugged into a Mac/PC it appears as an external USB disk and books can just be dropped on to the device. Once unmounted (ejected) the books are 'processed' and put into the library ready for reading. Trying both a ePub and MOBI version of the same book (O'Reilly tech book), though the Kobo would read both, the MOBI version caused the Kobi to become very sluggish and reacting to page changes or going back 'home' took a while. The ePub version reacted quickly without problems. PDF's were sluggish too and caused various bits of the screen to flash as pages loaded and moved between bits of the screen.

If you have an account on the Kobo store, it's easy to download a book, just find the one you want, tap on it and it will download.

It's also possible to borrow books from your local library (assuming there's still any left in your area) using the Overdrive service. All you need is a library card and books can be requested. You'll be warned (3 days) when the book needs to be returned, then you can re-request it if you haven't finished it. The list of libraries is available here.

Assuming you stick to ePubs it's not a bad eReader and being waterproof is a nice feature. It's a shame MOBI/PDF aren't handled better.

The Kobo Aura ONE is available on-line for £189.99 which is a lot cheaper the Amazon's top of the range eReader, but a lot more expensive than their basic ones, though it's bigger and more book like. Oddly the Kobo site doesn't have availability at the moment.