This is a Pentair Lock Ring for High Capacity Automatic Feeder, Dynamic Series Top Load Inline Cartridge Filter, Predator II Mini-Cellular Media Filter Systems, Leaf Traps.
This item is used with the High Capacity Automatic Feeder Model HC-3315; HC-3330; HC-3340; Dynamic Series 1 Inline Cartridge Filter Model RDC-25; RDC-25S; RDC-50 and RDC-50S; Predator II Mini-Cellular Media Filter Systems; Leaf Traps Model 179/179C; Dynamic Series Top Load Inline Cartridge Filter Model DSC 75; DSC 100 and Dynamic Series II and III Model RTL/RCF.