Pair of Lumia phones appear on Zauba's web site, could be the Lumia 840 XL
These could be the unannounced Microsoft Lumia 840 or Microsoft Lumia 840 XL, the successor(s) to the Nokia Lumia 830. In fact, with a 5.7-inch phablet-esque screen size, the odds favor this being the Lumia 840 XL. By the way, the Lumia 840 line will also support single and dual SIM capabilities.
While the Zauba listing shows that the device is in testing, it is possible that an unveiling of the new handsets isn't that far away. One anonymous Microsoft employee hinted last month that the Lumia 840 could feature a 5-inch screen, a 13-14MP rear PureView camera, 5MP front-facing snapper and a design similar to the Lumia 830.
source: Zauba via WMPoweruser