Fitbit is famed for its fitness trackers. However, it has released a pair of Bluetooth in-ear headphones that has largely flown under the radar. It is called the Flyer.

Unlike truly wireless headphones, the Flyer has a cable connecting the two earbuds. But it comes with an adjustable clip to reduce the bouncing of the cable on the back of a user's neck during runs.

The Flyer comes with three sizes of ear tips (small, medium and large) and two sizes of wings and fins (small and large). Two colours are available - blue (the version tested) and grey.

I found the default wing and ear tips (in medium size) to be a perfect fit for my ears. I did not need the extra fins. The Flyer stayed snugly in place during my workouts.

Each earbud has a nice metallic finish and hydrophobic coating for sweat resistance.

There is a three-button remote control - for volume control and answering calls - near the right earbud. The micro-USB charging port is also found on the remote.

To power up the Flyer, press the small button on the right earbud.

The Flyer does not come with fitness tracking ability, unlike Samsung's Gear IconX (2018), which The Straits Times reviewed last week. I find this quite surprising, considering Fitbit's fitness background.

While Fitbit probably wants users to use the Flyer with its first smartwatch Ionic, which has 2.5GB of music storage space, it is easy to use it with different devices.

It can remember the pairing information of up to eight devices. And it can be connected to two devices at the same time.

For this review, I paired the Flyer with the Ionic and my iPhone X, and the pairing process was a breeze. Just power up the Flyer and it will be available for pairing on the device's Bluetooth menu. Tap on the Flyer to finish the pairing.

The Flyer might be Fitbit's first audio product, but its audio output is surprisingly good, offering punchy bass with crisp mids and highs.

There is a Power Boost mode that can be activated by pressing and holding the volume up and down buttons at the same time. This mode, though, is for those who love nothing but bass. When I tried it, the bass was so overpowering that it distorted the mids and highs.

In addition, the Flyer shuts out the ambient noise well when music is playing. So, users might want to lower the volume when jogging to hear the surroundings.

For calls, I could easily hear what the other party was saying, even though the audio was slightly muffled. And I was told I sounded clear on the other end of the call.

In terms of battery life, Fitbit says the Flyer can last up to six hours of music playback a charge. Mileage varies according to usage patterns, such as if one is always cranking up the volume. I got close to the advertised battery life using it with my iPhone X.

• Verdict: If you own the Fitbit Ionic, the Fitbit Flyer is a natural choice. However, if you use your smartphone to listen to music during workouts, the Flyer is a great choice as well.