Perfect Dirt Barrier - The WOLTERS Cleankeeper Doormat. The WOLTERS Cleankeeper Doormat is a true dirt barrier. Thanks to numerous soft microfiber strands, the mat absorbs mud and water in seconds, which your dog brings into the house every day. It dries significantly faster than conventional mats. A rubberized underside prevents unwanted slipping. The doormat is ideal for the home, car, or dog crate. The mat can be washed individually on a gentle cycle at 30 degrees and should be air-dried.