Polaris 3900 Sport replacement filter bag. Polaris Part Number 39-310. This is the original factory replacement part designed for the Polaris 3900 Sport pool cleaner. It features double wings, each with their own zipper closure for easy cleaning.

The Polaris 39-310 Superbag is a large, double-chambered replacement filtration bag designed for the Polaris 3900 Sport or P39 pressure side vac-sweep pool cleaners. The 39-310 Superbag is gray in color and expands to hold up to 5 liters of large and small debris within the dual-zippered chambers, giving almost twice as much debris capacity as a single chamber Polaris pool cleaner bag.