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A shelf life in years, and no pore size in microns

GRAYL UltraPress replacement purifier cartridge, 300 cycles

A press cartridge that names its bottle exactly, publishes its life in cycles as well as litres, and never states the pore size that would let the rest of its claim list be compared.

GRAYL UltraPress black replacement purifier cartridge

GRAYL UltraPress replacement purifier cartridge, 300 cycles

A press cartridge that names its bottle exactly, publishes its life in cycles as well as litres, and never states the pore size that would let the rest of its claim list be compared.

Compatible housings
The maker's own UltraPress purifier and filter bottle of 16.9 fl oz — stated in the first bullet
Thread standard
Not published on the listing
Stated pore rating
Not published on the listing — the listing describes at length what the cartridge is claimed to handle, and gives no micron figure
Rated capacity
300 cycles, quoted by the maker as 40 gal./150 L — stated; unused cartridges are stated to keep for ten years in proper storage
Stated flow rate
Not published on the listing
Backflush method
Not published on the listing — a shelf life is published instead of a cleaning routine
Amazon reference
B09NYLCGTS (same reference on 6 Amazon marketplaces)
EAN
0850015512575
  • Names one bottle and gives its size in the same line, which leaves no room for a wrong order
  • Publishes its life two ways — in press cycles and in volume — so it can be compared with cartridges counted either way
  • No pore rating, on the most talkative claim list in this hub

Best for: Travel with an UltraPress, where a spare cartridge is stored ahead of the trip and replaced as a routine cost.

≈ $25 / £30 / 35 €
Check price on Amazon

Specifications

Compatible housings
The maker's own UltraPress purifier and filter bottle of 16.9 fl oz — stated in the first bullet
Thread standard
Not published on the listing
Stated pore rating
Not published on the listing — the listing describes at length what the cartridge is claimed to handle, and gives no micron figure
Rated capacity
300 cycles, quoted by the maker as 40 gal./150 L — stated; unused cartridges are stated to keep for ten years in proper storage
Stated flow rate
Not published on the listing
Backflush method
Not published on the listing — a shelf life is published instead of a cleaning routine
Amazon reference
B09NYLCGTS (same reference on 6 Amazon marketplaces)
EAN
0850015512575

What this listing puts on record

A cartridge stated to work with the maker’s UltraPress water purifier and filter bottle of 16.9 fl oz. A life of 300 cycles, quoted as 40 gal./150 L. A ten-year shelf life for unused cartridges kept in proper storage. Independent testing and laboratory certification to NSF protocols 42 and 53, cited by the maker. A long list of categories the cartridge is claimed to handle.

The fit line is exact, and that is the point

One bottle, named, with its size. No other cartridge on this shelf identifies its housing this precisely. It also means the listing rules out everything else by omission, including the GRAYL bottle reviewed elsewhere on this site, which is a different body of a different capacity.

A life counted twice

300 cycles, or 40 gal./150 L. Press cartridges wear by pressing, so a cycle count describes the work done better than a volume does — and publishing both lets this one be lined up against the litre figures the rest of the shelf uses.

Read the litre figure honestly: 150 is the shortest published in this hub, against 200, 500, 2000 and 4000 litres elsewhere. A cartridge is where the money goes on a press bottle, and this is the arithmetic that says how much.

Ten years on a shelf

An unused cartridge is stated to keep for a decade in proper storage. That is a figure almost nobody on this shelf publishes, and it is the one that makes a spare worth buying before it is needed rather than after.

Whose claims these are

The listing names viruses, bacteria and protozoan cysts with examples, and names particles, volatile organic compounds, PFAS, chemicals, pesticides, herbicides, heavy metals, tastes and odours. Every one of them stays in the maker’s mouth here: the maker states 99.9999 % of bacteria, and states the other percentages and categories it publishes. This page reports those statements and does not repeat them as findings, does not say what treated water may be used for, and does not say the opposite either. The maker’s instructions and the local authority govern that question.

Before ordering

Check the name moulded on your own bottle, not its shape. Then price a year of walking at 150 litres a cartridge, because on a press bottle that is the real cost of ownership.

Availability

Selling at about 35 € on the German, French, Italian and Spanish Amazon stores when this page was checked.

It also sells on the American and British Amazon stores in the local currency, which the range above does not cover — that range counts euro stores and nothing else.

Every figure in this section is what Keepa returned on the day this page was last updated. Prices and offers change without notice.

Prices quoted in this text were read on 6 September 2026. The live price is at the top of the page.

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