The vehicles are made by UNICAT, a company based in Europe that now also has an American branch.
The particular model shown in the photographs is designated as the "EX63-HDM / MAN TGA 6x6". The series of photographs included in the email can be viewed on the UNICAT website, along with many other photographs. This model has a roof that lowers snugly over the windows when travelling thus explaining the apparent mystery of the disappearing windows.
UNICATAmericas explains its philosophyas follows:
Our Philosophy: "Explore without boundaries"There are many RV's that will ably go anywhere where there are roads and even more SUV's, trucks, motorcycles, dune buggies, ATV's, etc. that will take you off-road. UNICAT bridges the gap by providing the highest comfort levels of an RV with a go anywhere ability of off-road vehicles.