Compared to the original Kärcher WD 3, this new model has new features that make maintenance and use a lot easier. The biggest advantage is that this model works both with and without a dust bag. This is very useful when you're vacuuming wet dirt. You don't have to work with wet vacuum cleaner bags, but only have to empty and clean the canister. This also makes it easy to use the vacuum for cleaning your garage or gutter. In addition, the included filter of this model is washable. This saves you a lot on costs, because you don't have to buy a new vacuum cleaner bag or filter every time.