Zipper that lasts longer than Velcro and won't clog. Large-capacity silt bag with reinforced seams and ultra-fine mesh to capture the smallest debris. Specifically shaped mesh to prevent debris from falling back when the robot cleaner is stopped. Hose attachment Velcro for easy passage of debris into the filter. Premium Quality: These nylon pool robot bag cleaning bags with strong seams and tights are woven. The fabric and weave materials are the same as Polaris 280/480. Can hold all types of debris: leaves, insects, twigs, sand and silt, hard to damage. Easy to Use: Extra-large zipper opening makes it easy to empty and clean debris in the filter bag. Easy to remove and install hook fasteners that can be removed for cleaning in seconds. Perfect Fit: This universal filter bag features extra-strong hook-and-loop fasteners designed to securely snap onto the pipe cleaner and close tightly at the top. A safe and secure closure provides total reliability. Best Compatibility: Works