Suunto are teasing the above image on Instagram and on Twitter.

The strap detail is like the SPARTAN SPORT BARO…and only the BARO …NOT the ULTRA and not the other SPORT variants.
The buttons and bezel look the same as several existing variants. So, maybe it’s a new product or variant.
Rather than speculating too much I’ll try to get some more and post later on today – best case scenario would be THE EQUIVALENT OF a SPARTAN ULTRA 2.0 with a new swappable strap, new watch faces, probably WHR and who knows what else? Note: I do NOT think here will be an ULTRA 2 with that name – I THINK Suunto might drop the SPARTAN name entirely eg Suunto 3, 4, 5 series.
You should also know:
- Suunto are rolling out new SPARTAN firmware, currently v2.0.40, details below. Some people have it, others not. So there could be confusion with this firmware version release and a possible ULTRA v2.
- Along with that there is a new manual for the SUUNTO SPARTAN ULTRA and SUUNTO SPARTAN SPORT listed as manual v2.0 (14 May 2018, possibly other models too). But this is firmware v2.0 and not a new model as far as I can see. Here it is from the Suunto site – .Suunto_Spartan_Ultra_UserGuide_EN
- Readers of the manual might get excited with the chip specs – SiRF star V – Resolution: 1 m / 3 ft. But that is the (same as) current variants.
Suunto Spartan software update 2.0 features
- New Zones – pace and power (just like the HR Zones)
- Enhanced workout traing targets – added duration/distance/intensity targets based on: heart rate (all activities); pace (running); and power (running and cycling, when a power pod is paired)
- Notification history: from the watch face just press the middle button to see all your recent notifications from your mobile device.
- Temperature has been added to the outdoor screen (Ultra and Baro models), found by navigating down with the lower right button or by swiping down.
- Suunto Spartans with Wrist HR now have the Instant HR display directly below the watch face display.
- Bug fixes and performance improvements including power management
Firmware Info Source: Suunto