Polaris Zodiac 3900 Chain Tensioner (39-120) lochinvar This version is especially useful

This version is especially useful when the supported system requires the longer 36 inch lead

and a 3/4 inch orifice

A lid like this is useful because it helps protect the strainer chamber while still allowing the user to access the basket area for cleaning and routine maintenance

Volute gaskets help preserve a pressure-tight seal between pump housing components and are essential to wet-end reliability

Useful when the original socket is damaged or worn

Polaris Zodiac 3900 Chain Tensioner (39-120) lochinvar This version is especially usefulPolaris Zodiac Chain Tensioner [3900] is a replacement part for compatible Polaris and Zodiac pool cleaner systems. This component helps keep the drive chain properly positioned so the cleaner can maintain steady movement during normal operation. When small cleaner parts wear out, even minor fit or movement issues can reduce cleaning coverage, create leaks, or cause the cleaner to move less reliably. Use part number 39 120 to help match this item to