InterFlo QuadPro SST
Tankless, high-efficiency RO with 4-year membrane life.
A sleek tankless reverse osmosis system that delivers purified water on demand — no storage tank taking up the cabinet, no waiting for a refill, and dramatically less wastewater than a traditional RO. Patented Superior SmartFlow dual-channel membrane resists scale from hard water and lasts up to four years between changes.
Households that want the best-tasting drinking water available, hate the wasted space of a tank, and don't want to think about filter changes more than once a year.
What you get
- Tankless design — frees up under-sink space
- 3 glasses of purified water for every 1 glass to drain (high efficiency)
- Patented dual-channel RO membrane, up to 4-year life
- 12-month carbon and sediment pre-filter
- LED faucet indicator shows filter life at 100 / 5 / 0%
- Self-calibrating keyed cartridges — two-step swap
- Certified to NSF/ANSI 58 by WQA (Gold Seal)
Specs at a glance
- Stages
- 3-stage tankless
- Membrane life
- Up to 48 months
- Pre-filter life
- 12 months
- Efficiency
- 3:1 purified-to-drain
“It's the best drinking-water system we've ever installed. Uses a fraction of the water of a classic RO and the cartridge changes take under a minute.”
— The Sawtooth team
Other Drinking Water we carry
See allHague H3500 Reverse Osmosis
Premium 4-stage RO with the longest membrane life we sell.
DetailsNelsen · ValueNelsen Aqua Classic Reverse Osmosis
Proven under-sink RO with a pressurized storage tank.
DetailsInterFlo · ValueInterFlo IF-14 Drinking Water Filter
Single-cartridge under-sink filter for great-tasting cold water.
DetailsInterFlo QuadPro SST — common questions
What buyers ask us before they choose this system.
How does reverse osmosis work?
Water is pushed through a semipermeable membrane that blocks dissolved solids, nitrates, lead, and most contaminants while letting water molecules through. Pre-filters catch sediment and chlorine before the membrane, and a carbon post-filter polishes taste on the way to the faucet. Filtered water is held in a small tank under the sink so it's there when you need it.
How often do RO filters need changing?
Pre-filters and carbon post-filters are annual on most systems. The membrane itself lasts three to five years, longer if the water is softened first — hardness is the main thing that shortens membrane life, which is why we usually recommend the softener and RO together.
Does reverse osmosis remove nitrates from well water?
Yes, and that's a real consideration in agricultural parts of the Magic Valley where nitrate levels in private wells can exceed the 10 mg/L drinking water standard. RO is one of the few point-of-use technologies that reliably reduces nitrates. If you're on a well and haven't tested for it, we'll include it in your free water test.
Can RO be plumbed to the refrigerator ice maker?
Yes — that's one of the most requested add-ons. We run a dedicated line from the RO tank to the fridge so ice and chilled water come from the same filtered supply. It's a straightforward addition during install and can be retrofitted later.