Wearables company Tzukuri has developed a new type of sunglasses that are described as unloseable, and they're now available for pre-order.

Relying on tracking beacons embedded in the frame, Tzukuri's smart sunglasses make use of Apple's iBeacon technology in order to pair with a nearby iPhone and ultimately pipe notifications to the phone about their whereabouts. In fact, when you leave the shades behind, an alarm will ring on your iPhone.

Apple's iBeacon technology allows Tzukuri to take advantage of Bluetooth Low Energy as well as geofencing, thus enabling micro-location awareness and notifications for the smart sunglasses. The notifications will even go off every 15 feet, as you move farther away from the sunglasses.

Once you realise the smart sunglasses are missing or not anywhere nearby, you can open the Tzukuri app to see their last location on a map. Simples. Tzukuri of course has assumed that you always have an iPhone on your person, even when or if you misplace sunglasses.

As for the sunglasses' design, Tzukuri said it analysed thousands of faces to design frames that they would suit the largest range of face shapes. The final six designs were even inspired by iconic figures, apparently, such as US President John F Kennedy.

These smart sunglasses are handmade in Japan and available in two colours (black and tortoise) and three sizes. Tuzukuri will only offer a limited run of 5,400 pairs, with each pair costing $249 USD, and then you can expect the price to increase to $349.