Polaris Zodiac 3900 Chain Tensioner (39-120) hydrodynamic and this 4

and this 4

A valve body assembly helps form the main housing structure of a compatible multiport valve

Designed for E4 Value Bath panel layouts

helping protect internal components while also contributing to the unit’s overall shape and water-handling behavior

Polaris Zodiac 3900 Chain Tensioner (39-120) hydrodynamic and this 4Polaris 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