is the original factory replacement for Filstar XP2 and API Filstar M.
Includes a new shaft and bearing/bushing. The rotor is the magnet part
of the motor that spins. Attached to this is the impeller which consists
of blades that catch and pump the water out of the filter and back to
the tank. Over time the rotor magnet loses magnetic strength and will
exhibit trouble starting or the filter will have reduced flow even after
the unit if your filter exhibits these symptoms or if the impeller
blades break or separate from the rotor. If you have the rotor/impeller
assembly with bearings at both ends, you can purchase these bearings
separately, item 440308-00.