(Pocket-lint) - If some premature Amazon listings are anything to go by, Garmin is a few weeks away from launching its next range of flagship Fenix watches.

The two top tier upcoming Fenix watches include the 6X Sapphire and the 6X Sapphire Solar, with the latter adding an even more premium model to expand the range.

In context of previous flagship watches, the X is the biggest, most powerful watch in a series that also includes an S (the smallest/cheapest model) and the regular model, all of which also have a Sapphire edition.

These listings indicate a few new very welcome features, particularly for runners, but the Fenix will remain the multi-sport champ of Garmin's product lineup.

First, there's the larger 1.4-inch screen surrounded by a stainless steel, titanium or diamond-like carbon bezel, with physical buttons to control the UI on both the left and right of the watch face.

As well as the big screen, the 6X models will also feature a new, enhanced heart rate sensor, but perhaps the biggest new addition isn't hardware based.

Pacepro is mentioned in the product listing, which adjusts your pace guidance during your activity based on the grade of hill you're on.

Typically, while monitoring your runs, pace guidance and Vo2 Max calculations don't take hills into account at all on current models. Which can be a little frustrating at times, especially when you run in hilly areas.

As usual, the watches will use GPS, GLONASS and Galileo satellite location support, with built in maps, sensors for a 3-axis compass, barometric altimeter and a gyroscope for movement.

Music storage is an option too, as is Garmin Pay, the company's contactless payment system.

Now on to the most exciting reveal in the listing - Sapphire Solar. As the name suggests, this model includes the ability to keep its battery topped up using the power of the sun.

The 6X Sapphire Solar's listing specifically mentioned solar charging, which might not be necessary for 5k/10k runners, but for those who take on more extreme challenges, knowing that your watch battery is recharging as you make your way around an ultra-marathon course will offer more peace of mind.

As for prices, the listings shown for the 6X Sapphire and 6X Sapphire Solar indicate these two models will be $949 and $1,149 respectively.

It's worth remembering however, that Sapphire models - those coated with a more durable sapphire crystal display - are more expensive than the regular versions.

If Garmin follows its own tradition, you can expect to see not only the cheaper 6S and 6, but also 6X without sapphire. As always, we'll keep you up to date when official word is out there.

Writing by Cam Bunton.