Spectra Watermakers
Spectra Watermakers 4 x 40 in Seawater Membrane and Seal Kit KIT-MB-4X40SW
$928.00
Manuals & support
Start with your model’s parts diagram and the number on the installed part. Match any model, controls, voltage, or serial-range notes shown in this listing.
Spectra / Katadyn manufacturer support ↗Overview
Overview
KIT-MB-4X40SW is a seawater reverse-osmosis membrane kit for Spectra’s documented 4-inch-diameter pressure vessels. It is a different size from the 2.5 × 40-inch kit even though both elements are described as 40 inches long.
The Farallon 2800C fact sheet specifies three 4 × 40-inch elements. Replacing that complete original membrane set requires three individual kits; replacing one element requires one. Use the configuration references for other Farallon and landbased arrangements.
Specifications & Contents
Specifications & Contents
| Part number | KIT-MB-4X40SW |
|---|---|
| Element size | 4-inch diameter × 40-inch length |
| Supplied | Seawater RO membrane and replacement seals; FilmTec or equivalent as specified by Spectra |
| Drawing reference | FT-MB-SW4X40 identifies the corresponding element in the reviewed parts diagrams |
| Order basis | One kit per individual element; three for the standard Farallon 2800C set |
Fits My System
Fits My System
Identify the 4-inch seawater vessel, its end-cap generation and the installed element count. The listed connections apply to those specific arrangements; they do not include 2.5-inch or 8-inch vessels.
Select your configuration to see its requirements, or open the complete reference below.
All documented configurations and requirements
Each group applies only to the listed configurations and installed hardware. Match the conditions and manufacturer references before ordering.
Documented configurations
- Aquifer 3000-MIL · Manual · Match installed voltage and hardware
Aquifer 3000-MIL configuration documented by the January 2026 manual; do not transfer to smaller Clark-pump Aquifers.
Documented configurations
- Farallon 1800 · MPC 5000 · Match installed voltage and hardware
- Farallon 2800 · MPC 5000 · Match installed voltage and hardware
For the original 4-inch-diameter x 40-inch seawater membrane arrangement identified as FT-MB-SW4X40 in this model parts diagram. KIT-MB-4X40SW is the current 4 x 40 replacement membrane and seal kit. One kit replaces one element; count the installed elements needed for your repair and match the vessel/end-cap generation. This is not the 2.5 x 40 kit or an 8 x 40 element.
Documented configurations
- Farallon 2800C · Connect · 220 VAC · Standard / long membranes · FL-2800C-220
Farallon 2800C, original standard / long membrane arrangement: 3 4-inch diameter x 40-inch membranes installed. Each KIT-MB-4X40SW kit replaces one membrane and includes seals; replacing every original element requires 3 kits. Match the installed vessel and end-cap/seal arrangement. This does not cover a modified membrane arrangement or the other diameter/length.
Documented configurations
- LB 1800C / 1800F · Connect · Match installed voltage and hardware
- LB 2800C / 2800F · Connect · Match installed voltage and hardware
- LB 4000C / 4000F · Connect · Match installed voltage and hardware
For the original 4-inch-diameter x 40-inch seawater membrane arrangement identified as FT-MB-SW4X40 in this model parts diagram. KIT-MB-4X40SW is the current 4 x 40 replacement membrane and seal kit. One kit replaces one element; count the installed elements needed for your repair and match the vessel/end-cap generation. This is not the 2.5 x 40 kit or an 8 x 40 element.
Documented configurations
- LB 1800M · Manual · Match installed voltage and hardware
- LB 2800M · Manual · Match installed voltage and hardware
For the original 4-inch-diameter x 40-inch seawater membrane arrangement identified as FT-MB-SW4X40 in this model parts diagram. KIT-MB-4X40SW is the current 4 x 40 replacement membrane and seal kit. One kit replaces one element; count the installed elements needed for your repair and match the vessel/end-cap generation. This is not the 2.5 x 40 kit or an 8 x 40 element.
FAQs
FAQs
Will any 40-inch membrane fit?
No. Diameter, seawater duty and the vessel arrangement all matter. KIT-MB-40F and KIT-MB-4X40SW are separate sizes.
