1.Package includes: 1x 1 x Gear Mechanism, 1 x Outer Casing Kit, 1 x Locking Ring 2.: This upgraded backup valve features a crackresistant polymer blend shell, making it twice as durable as previous models. It improved wear resistance and is less prone to damage. 3.Check for Maintenance: First, check for any damage to the filter. If the filter is fine, open the backup valve and clean any impurities from the gear. 4.Compatibility: The 91001200 InLine Backup Valve is compatible with Polaris 360 and VacSweep 360 pool cleaners. If high water pressure causes the valve to get stuck in standby mode, simply remove the spool and lightly grind the guide tube's curved surface to release the pressure. 5.Upgraded mechanism: The gear mechanism is crafted from POM material, known for its wear resistance and stability. It can operate continuously under high water pressure but may become stuck if excess sand accumulates. Simply remove the grinding wheel to clean the sand and resume use.