Product imagery from Sentry H2O.
Sentry H2O Portable System Replacement Filters
Old media = unfiltered water on the go.
Free Ground shipping on every order, contiguous US. No minimum.
Usually ships within a week. Sentry H2O ships orders on Mondays and Thursdays.
Standard: ToxyGuard & AlkaGuard Filters.
Order detailsStandard refill
- Plug & play
- 30-day returns; restocking fees apply
- Filters & filter media are consumables
- Free Ground shipping on every order, contiguous US
- Checkout hosted by Shopify
- Lifetime product support
Why it matters
The Portable System Replacement Filters, in short.
Fresh media, clean water on the road. Standard is for known treated water; the Premium refill includes BioChemGuard + AlkaGuard for emergency and uncertain sources. Replace at 12 months or 3,000 gallons, whichever comes first (per installed filter set).
The details
Specifications
Specifications reflect the manufacturer (Sentry H2O). See our Science page for published independent lab reports and testing gaps. We do not call the complete systems NSF certified: Sentry H2O uses tested or certified components where applicable.
Sentry H2O · Replacement filters
Sentry H2O Portable System Replacement Filters
Sentry H2O systems are built to last years — the filter change is what keeps them performing like day one. Subscribe once and the exact set arrives every 12 months at 10% off, or buy a one-time set.
Subscribe & save is selected in the purchase options above: every 12 months at 10% off. One-time purchase is there too.
Eligible purchase options are shown above; if subscription is unavailable, choose a one-time purchase.
Straight answers
Common questions
Is the Sentry H2O Portable System Replacement Filters right for my home?+
Sentry H2O Portable System owners. Not sure? Our 60-second quiz confirms fit in a minute.
How often do filters need replacing?+
12 months or 3,000 gallons, whichever comes first (per installed filter set). Auto-ship on the refill page renews the exact refill every 12 months at 10% off; replace sooner if your usage reaches the rated gallons first.
What if it is not right for me?+
Contact Mountain Pure Water first at (435) 990-3778; we issue the return instructions before you send anything back. Eligible refills may be returned within 30 days after delivery; restocking fees apply. Filters and filter media are consumables; see our Shipping, Returns & Refunds policy for the full terms.
How do I handle a return, shipping damage or a warranty claim?+
Contact Mountain Pure Water first at (435) 990-3778 with your order number and details of the issue; include photos for shipping damage. We coordinate the review and issue any return instructions, including the correct destination. Wait for our instructions before sending anything back. Shipping damage, including broken fittings, is reviewed case by case. See our Shipping, Returns & Refunds policy for the 30-day return window, restocking fees and warranty terms.
Is shipping free?+
Free Ground shipping on every order, contiguous US. No minimum. Shipping is $10 to Alaska, Hawaii and Puerto Rico. We ship to US addresses only. See our Shipping, Returns & Refunds policy for details.
What is catalytic-carbon filtration, and how is it different from reverse osmosis?+
Catalytic-carbon filtration uses specially processed activated carbon that reacts with and breaks down contaminants as water passes through multiple stages. Unlike reverse osmosis, our Sentry H2O systems don't strip the water of everything -- they target the bad stuff while leaving naturally occurring beneficial minerals in place. The non-RO city filtration stages produce no RO reject-water waste.
Does the system need electricity or produce wastewater?+
Our non-RO city filtration stages run on water pressure and produce no RO reject-water waste. UV accessories require power. Well treatment may produce waste or backwash water; requirements depend on the selected configuration.
Real customers, real water
Review evidence for this product
Product relevance is stated explicitly; unrelated excerpts are never substituted.
Sentry H2O store review snapshot, independently collected by Judge.me, as of August 2026.
Sentry H2O Portable and bottle family reviews
These reviews cover products in the Portable and bottle family, not this exact configuration. Each card names the product reviewed.
August 2026 review-count snapshot.
Rating, count and verification rate checked on Judge.me September 15, 2026.
See the Sentry H2O store reviews →Review of SENTRY PORTABLE SYSTEM
No More Filling Carboys!
My husband and I have now purchased 2 Sentry filtration systems… one (home) under-the-sink kitchen mount and one portable for our RV. We’d spend the last couple of years filling 5 gallon carboys with drinking/cooking water as the municipal source is unacceptable, so this has proven to be a great solution for us and such peace of mind!
Review of Sentry H2O BioChem OTG Bottle
Love the water bottle
I love the water system and shower filter. Huge, huge difference. I then purchased the water bottle, love that as well. I take it with me to the restaurant and put the water in to filter out the chemicals. Big thumbs up on this entire system.
Know your water
Know what is in your water before you choose a system.
Start with independent findings for your area, then match your home to the right Sentry H2O system.
Read your local water report
Your area's annual Consumer Confidence Report (CCR) lists what has been detected in your municipal tap water.
Salt Lake City? See what's really in your water →Check the EWG Tap Water Database
Enter your zip code for a plain-language breakdown of the contaminants found in your local supply.
Open the EWG database →At-home test kit (for well water and specific concerns)
Use our mail-in well-water kit when an individual result makes sense for your source or concern.
Shop the well-water kit →Want help matching the result to a Sentry H2O system?