Pentair - L-Gasket for Balboa and Pentair Spa Jet Sockets - 959000

Pentair – L-Gasket for Balboa and Pentair Spa Jet Sockets

The Pentair 959000 L-gasket is a replacement hot tub gasket for many Balboa and Pentair sockets, including the Slimline 3.5″ and Micro Cyclone series. Its L-shaped profile is the key difference from a simple flat gasket, and it sits in the opening in the spa shell.

Compatibility with Balboa and Pentair sockets

This L-shaped spa gasket is suitable for many sockets from Balboa and Pentair. The source specifically names the Slimline 3.5″ and Micro Cyclone series, so these are the first places to look if you are replacing a worn seal on one of those fittings.

Balboa and Pentair list the same part number for this gasket, 959000, so you can search under either brand name.

Fitting and dimensions

The gasket sits in the opening in the spa shell. When it is installed correctly, the L-shaped design gives a more reliable seal than a simple flat gasket.

• Outside diameter: 66 mm
• Inside diameter: 50 mm

If you are also working on the fixing hardware at the same socket, the Pentair Slimline jet body nut is available as a separate part.

How to choose the right replacement gasket

Because this is a seal and not a complete fitting, the profile and size matter. Before ordering, check these points against the gasket you are replacing:

• The gasket is L-shaped, not flat.
• The outside diameter is 66 mm and the inside diameter is 50 mm.
• Your socket is a Balboa or Pentair model, such as the Slimline 3.5″ or Micro Cyclone.

If your old gasket is flat, or the measurements differ, do not assume this part will be a match. Compare it carefully with what is installed in your spa shell first.

Part number and ordering

The part number for this L-gasket is 959000, listed under both Pentair and Balboa. Quote it when you compare parts or ask about your spa.

This page covers the gasket only. Other parts that belong to the same socket, such as nuts or fittings, are sold separately.