Max Water 4" x 40" BW-4040 / TW30-4040 2400 GPD Brackish Water RO Membrane Perfect for Car Wash, Whole House & Industrial Applications | Compatible with AG4040FF, RE4040-BE and more

I bought these for my reverse osmosis system and it has been working with amazing results.

Works very well. First one lasted almost a year with nasty well water.

A lot more RO Water, and less water sent down the drain. Replace the 21 inch.

Pretty impressed with the quality for the price, came with mounting straps also, works great, no complaints.

This product is excellent i got it on time like they say and in order no damages I'm a happy customer and will purchase again and will recommend this product to family and friends

The first time I used the pair of membranes, since I bought 2 of them to double water output, they worked great. My local municipal water has tds levels in the 500-750 ppm range with most days being in the 500-600 range. In the first month, my permeate ppm range was between 0-15 ppm at most, and didn’t use DI resin much to wash cars or my solar panels. Unfortunately, after 6 months of use, my permeate has steadily increased from the 0-15 ppm level to 80-95 ppm. It still removes about 80% of tds, but 20% leakage is already telling me that it’s time to replace what are lightly used membranes. I use a 20x4.5 sediment filter, and a 20x4.5 carbon block filter to ensure that no elements that can ruin these membranes get through. My usage is mostly for washing 1 or 2 cars, and periodic solar panel cleaning during the weekends, meaning that I use less than 100 gallons of permeate in each weekend event. Membranes are kept wet, and not used for drinking, even though I would feel comfortable drinking from them. Operating pressure ranges from 50 psi (municipal) to 120 psi via pump for pressure boosting when needing to increase water output. I didn’t think it would be fair for me to write a 1 or 2 star review without giving the seller a chance to respond first, privately through their website, but after 3 weeks, and no response from them, I believe that it’s fair to share my experience with anyone interested in considering this commercial RO membrane. I’ll be looking for a different manufacturer, even if I have to pay an extra $100 dollars for 2 membranes of the 4x40 size. By the way, the plastic end-caps cracked, even though I didn’t torque them much. The leaks are not from the circumference, but from the threaded fittings. I have replaced 8 caps at my own expense, and the last 4 are not leaking, but they required lots of teflon and a gentle hand to avoid cracking them. The cracks are almost not visible with the naked eye, but you’ll see the water leaking when pressurized, and they come from the threaded holes closes to the edge for the most part. I would suggest that it may be best to create a metal end cap. I’m sure it will be heavier and more expensive, but it will last a long time, and I care more about reliability than disposability. Unfortunately, plastic runs the risk of cracking each time the end caps are removed to service the membranes since the seals are tight. A metal end cap can take more punishment without cracking, and it’s a once and done deal.

excelente a buen precio

Great value and quality product.