Review on Hongfa 12-Pack Replacement Filters for iRobot Roomba s9+ s9 s9 Plus, Compatible Replacement Parts for Roomba S9+ (9550), S9（9150), Roomba S Series by Turbo Jiles

Filters fit perfectly. I'm not sure if this was just an oversight by iRobot or an attempt to boost sales of their expensive HEPA filters, but HEPAs are designed to filter extremely fine particles, not the large dust and debris that Roomba collects . While filters do a great job of stopping dust from returning to the air, these filters are designed to be used with a pre-filter to capture larger debris due to premature HEPA clogging. This is to ensure your Roomba is always running at peak performance. , it is extremely important that this filter is clean and has good water passage. Roomba replacement filters are insanely expensive as I believe these filters should be changed at least weekly for daily use. Obviously it's going to be insanely expensive so I'm glad I found this product. Inexpensive, the equipment is perfect, the filters do their job well.