Primary Permatex Filter for 356mm Machine 604116 - NumaticGenuine Replacement 356mm White Filter If you have a 356mm vacuum cleaner from Numatic and are finding the suction is not as good as it once was, and have already replaced the bags it may be time to change your secondary filter. This basket filter is the last stage of filtration after your dust bags in your vacuum cleaner, it sits on top of the drum and prevents dust from escaping the vacuum cleaner and protects the motors from foreign object. If this