Description

This is the Pentair clamp ring assembly, part 191805, for PacFab Nautilus Plus DE filters. Pentair paperwork also calls it the clamp band. It covers the Nautilus Plus INS24, INS36 and INS48 models.

What the ring does

The clamp ring is what holds the upper and lower halves of the filter tank together against system pressure. It sits outdoors, in and out of water, for years, and when it corrodes or the hardware seizes it becomes both a leak risk and a job you cannot finish, because the tank will not come apart or go back together properly without it.

Genuine part

This is the Pentair OEM assembly, matched to the Nautilus Plus tank rather than a universal band trimmed to fit.