However, the prerequisite for optimum performance and maximum durability of Motorex air filters is regular maintenance. The filters need to be cleaned by steeping them in the Air Filter Cleaner immersion bath, after which they are oiled with Air Filter Oil 206. Both products have now been thoroughly revised in the Swiss Motorex lab. The new packages are recognized by the new label which also contains specific instructions for use. In addition, Motorex dealers stock the free brochure "Air Filter Cleaning Guideline" with a clearly description of the process. Finally, there is even a video guide here: www.youtube.com/motorexoil. Air Filter Cleaner is free of solvents, bio-degradable and non-combustible. Like the Air Filter Oil 206, the cleaner can be re-used for the next filter maintenance.