Filbur FC-9430 Partial DE Grid for 36 Sq. Ft. Pool Filter Zodiac R0635400 Top Housing Cover (Blue) for Polaris 360 & 360 Black Max Cleaner Pre-stretched at the factory so

Pre-stretched at the factory so it works longer without needing to be adjusted

Two prongs on the head of shell prevent the anchor from rotating during expansion

Not just an added ring

Permatex Anti-Seize Lubricant is a blend of aluminum

Filbur FC-9430 Partial DE Grid for 36 Sq. Ft. Pool Filter Zodiac R0635400 Top Housing Cover (Blue) for Polaris 360 & 360 Black Max Cleaner Pre-stretched at the factory soFilbur FC 9430 Partial DE Grid for 36 Sq. Ft. Pool Filter Specifications: Filter Total Number of Grids Required: 8 Total Grid Size (l x w) Type Qty Required: 18" x 9 3 4" Partial (1 reqd) Filbur Number: FC 9430 Unicel Number: PG 1903 Grid OEM Number: 11620R4200, 59001700, 818 3940, DEX3600DS