Snap has unveiled the fourth generation of its Spectacles, complete with long-rumoured augmented reality capabilities built into the frame.

The new smartglasses are the company's first to offer a more advanced AR experience, and they're also the first iteration not available to buy. 

Snap CEO Evan Spiegel debuted the frames at the company's Partner Summit event, which also feature two cameras, four microphones, touchpad controls and a pair of stereo speakers.

The glasses are able to connect directly with Snapchat's library of AR Lenses and the Lens Studio Platform, and offer wearers the chance to "realistically ground digital objects in the physical world," Spiegel said.

"Spectacles understands what's in their field of view and suggests relevant Lenses based on what's around you. You can then snap the scene and send it to your friends to share the full picture," Spiegel continued.

Snap's latest Spectacles let you experience the world in augmented reality - but you can't buy them yet photo 2

Instead of being available to Snapchat users, like past models, Snap will instead be handing them to an undisclosed number of AR effect creators through an online application programme. The idea, then, is for the fourth-gen Specs to be in the hands of users best-placed to take advantage of the new AR tech and, likely, create some buzz for future versions.

After all, built-in AR glasses are still in very tentative stages - the new Specs, for example, only have a battery life of approximately 30 minutes, which is another reason why they're not cut out for the mass market.

Spiegel suggested during the announcement that AR glasses will take roughly a decade to reach mainstream adoption. Given its continued commitment to providing users with camera-related, wearable experiences - something that's entering more intriguing territory with this latest generation - expect Snap to be at the forefront of that adoption with the likes of Facebook.