Pentair FNS Plus Filter Lid Assembly, 48 sq ft | 170021 Smart Company Physical role: Sits inside the

Physical role: Sits inside the diaphragm housing to provide a flexible seal that responds to system pressure changes

xm systems and certain in

then folds down for compact storage

and help maintain consistent pressure across your filtration system

Pentair FNS Plus Filter Lid Assembly, 48 sq ft | 170021 Smart Company Physical role: Sits inside theWhat This Part Is Used For Pentair 170021 Lid Assembly 48Sqft, FNS Plus is a replacement lid for compatible FNS Plus 48Sqft filters. It covers and seals the filter tank. Why This Part Matters Maintaining a proper seal prevents pressure loss and water leaks. A damaged lid can disrupt filtration efficiency. Replacing it helps restore consistent filter performance. Key Features and Specifications Pentair manufacturer part number 170021 For FNS Plus