iSpring F28K75 NSF Certified 3-Year Replacement Set for 6-Stage Reverse Osmosis RO Systems with Alkaline Mineral Filter, 28 Pieces, White

I’ve been using iSpring filters for 4 years, and this 3-year replacement set is definitely worth it and saves money when buying in bulk. The parts are well-made, easy to swap out, and instantly improve the taste of our water. I love that everything for the full 6-stage system comes in one kit, and the NSF certification gives extra peace of mind. Reliable, long-lasting, and a solid value, highly recommend for anyone running an iSpring RO system.

After about 13 months of use with my NON-iSpring 6-stage RO system installed last year by a local vendor, the water taste had noticeably changed. By then, I'd been trying to schedule for weeks a date/time with the same vendor for filter replacement. When the tech finally came, he didn't have the alkaline filter with him... I said goodbye to him, and onto Amazon I went. These filters fit perfectly with my RO system. This is by far the best bargain for RO filters, and even includes a replacement membrane (replaced every 3 years). The local RO shop charges ~$150 to replace the 6-stage filters annually (not the membrane), and that's with the "6 months" filters being used for 12 months, and since iSpring's includes 6 of the "6 months" filters, it's an even better value. And you can replace the filters at your own convenience. Only caveat was I had to call iSpring to request 4 free quick-fit adapters to thread onto the stage 5 & 6 filters (my previous ones had quick-fit built into the filter cases), with several wraps of Mr. Gasket 2842G Teflon Tape (can leak otherwise). Phone support was very prompt and helpful. Check YouTube for simple "RO filter replacement" videos. You'll want to clean the Stage 1-3 filter canisters (the big vertical ones), since they get grimy after a year. If you don't already have a horizontal mount for the stage 5 or 6 filters, I'd recommend S5-TO-S6 RO Kit for 2.5" diameter Inline Filter (buy 2 if you need a pair for both filters), which will keep the stage 5 & 6 filters stable and less prone to hose leakage. --- [Update 02/02/2016] I just replaced replaced the second set, and water's still awesome. A friend had even commented how good our water tastes, although we didn't even mention our R.O. system!

This is really your best bang for your buck the three year filter supply. The ispring unit is awesome. I am so glad I purchased it five years ago. The company is great to deal with you really just can’t go wrong. It’s cheaper than most local water places and it works great thank you “Nick” for your outstanding customer service when I called with a question.

Update 7/8/2021: This set came with a tiny packet of fittings for a slightly new style of final carbon filter. I missed it buried at the bottom of the big box. Called iSpring. They sent one priority mail (Thanks Don!). Now I feel bad because I had one after all. These folks are terrific. Replaced all filters including RO. Other than just not seeing the tiny packet, no problems. We have a 6 year relationship with iSpring (123filter.com), bought our 6-stage undersink RO unit in 2014, and I can't say enough good about the company and their systems. Divide the price I paid for these filters by the 36 months they are going to last? That's $4/month for all the water we'll ever need, we even water our plants and our pets with it. Next I get the ice cube kit. Our E. Texas water makes coffee taste like soap, plus, I'm just not seeing the numbers I'm looking for in the quarterly reports from the water dept., but why worrify? Just purify. Over 6 years things break. A nylon union split. A filter housing sprung a pinhole leak. The end of a Teflon tube got too chewed up by a quick-disconnect fitting. Hey, the whole thing's under pressure and pure water just wants to dissolve, dissolve, dissolve, so no big surprise there. We set our unit in a turkey roaster pan just so a minor leak won't wet our kitchen throw rug. If there is one, it's quick to spot, and iSpring is tops at customer support. Water was running slow. Back to the manual. All we needed to know we found in one tiny troubleshooting paragraph. A bicycle pump, a tire gauge and a half hour, and the water was back to running gushers. If you or someone you know is the least bit handy, and if you hate big monthly costs as much as we do, iSpring's a no-brainer.

Great filters. Always go with genuine replacements. Nick at 123 filters answered all my questions promptly. Thank you!

Great product and was easy to install. Arrived on time and is working great!

This box has everything you need to keep your iSpring filter running for 3 years. Of course you could stretch things out a little longer but the price can't be beat to just do it on schedule. My town supplements the water supply in the summer with well water and this filter makes quick work of it.

Either use these filters to clean the drinking water or your kidneys. ISpring filters work great. But -yes there is a but- when you see just how much yuck these filters capture you will change them more often than the "recommended" schedule.