I am not quite sure. I have the WG629E.91. The only difference I can see (I think) is that mine came with more accessories. 1x multi spray nozzle, 1x long extension, 1x short extension, 1x foldable bucket, 1x brush tag, 1x soap dispenser, 1x hose delivery, 1x net bag. I believe the pressure is the same with 22bar. I know that in other countries there is a 40V version to which you can connect 2 batteries. I would recommend the 4.0Ah battery for longer runtime. As a reminder, I would like to clarify that this is not a real high pressure cleaner. It is great for washing, light cleaning, and for use where there is no water tap or electricity nearby.