SuperPro Generic Tank O-Ring 19-1/4″ ID (1/2″ Thick), O-333-9

The SuperPro O-333-9 is a generic filter tank o-ring measuring 19-1/4 inches inside diameter with a 1/2 inch thickness. It is the third party version of the Pentair 071439, made by SuperPro and Aladdin.

What it seals

A tank o-ring sits between the two halves of a filter body and is what the clamp squeezes to hold system pressure. When it flattens, hardens or takes a nick, the tank weeps at the seam and the leak usually gets worse the moment the pump starts.

Getting the right one

Tank o-rings from different years look almost identical, so size is what matters. This one is listed for filters built between March 2003 and July 2003. Measure the old ring across the inside and check the thickness before ordering, and cross reference the numbers 071439, P24218, O333 and 71439 if your paperwork uses one of those instead.