With this version of the Kärcher WD 3 V-17/4/20, you receive 4 extra vacuum cleaner bags. You have a supply right away and won't be without vacuum cleaner bags this way. Compared to the original Kärcher WD 3, this new model has new function that make it easier to use. The largest advantage is that this model works both with and without vacuum cleaner bag. This is very useful if you vacuum wet dirt. Take the vacuum cleaner bag out and vacuum the dirt and collect it directly in the container. This way, you can also use the vacuum for cleaning your garage or gutter. The included filter of this new model is washable as well, so you have to replace it less often.