Seems that, our guess about that “Mars” device leaked today may actually be right. After RM-941, second variant RM-942 has also passed through FCC. This variant has 4 LTE frequencies. It supports both AT&T and T-Mobile LTE bands. Now, it seems RM-941 was the global version and RM-942, which has all US carrier’s LTE bands is the US variant after all.
This is an LTE Category 3 device; it contains four LTE bands, namely LTE bands 700, 850,1700/2100 and 1900
It has similar dimensions as of RM-941 and according to our calculation, it seems it will have size of 128.6 X 70 comparable to 127.9 x 67.9 of Lumia 720.
So, now it hardly seems surprising that O2, Germany document has two devices listed for July-August release.
RM-941 / RM-942 both passing through FCC shows that it will be unveiled along with or just after Lumia 1020 aka RM-877 / RM-875.