Hello Porsgrunn. A DMT8EE is a diamond plate that one uses for light honing. It is 3micron grit plate. It does not need lapping which is a process that one has to go through if using a stone because whatever you use for honing a razor it must be flat. A four sided strop is a paddle that has four leather sides to it. On each side is a diamond paste that you use for finishing a razor after it comes off the hone. I have 3.0,1.0,0.5,0.25 micron pastes on each of the different sides. "The Well Shaved Gentleman" is run by a fellow named Tony who does really good work on strops, but he is in the USA. I would think there are people in Europe who do about the same work but not quite the quality of Tony
If all this is new to you then you probably need to have your razor outside honed but there is still the question of taking care of the edge. I really think the pasted strop is the answer for the average guy that doesn't want to be a honing master.
Do searches on this site and read a lot and you will find out what you need to know for the most part.

Good luck,
Richard