Retention hours only compare when the stated conditions match · review
A 1 liter flask supplied with a natural-bristle brush and a carabiner, whose single retention figure of 13 hours is never split into hot and cold.
A 1 liter stainless bottle in stated 18/08 steel, supplied with a natural-bristle cleaning brush, a jute bag and a trekking carabiner, stated leak-proof and stated to suit carbonated drinks.
The listing states the water temperature is held stable over 13 hours. It does not say hot. It does not say cold. It does not say both.
Six flasks in this hub quote a pair — typically 12 hours hot and 24 cold. One figure that refuses to name its direction cannot be placed against either half of that pair, so this page reports it as published and leaves both lines unfilled.
Nothing in the title or the bullets says double wall, and nothing says vacuum. The word used is insulated. On this shelf that is the one claim everybody makes and almost everybody qualifies.
A natural-bristle brush — the only one supplied anywhere in this hub — a jute bag and a carabiner. The maker also commits to sending a replacement or finding another solution if the bottle leaks, and states a 60-day money-back offer.
The brush comes with it and the opening it fits through is not dimensioned. If you want to use a brush you already own, nothing on the page will tell you whether it goes in.
The American Amazon store was listing it at about $33 at the time of writing.
Every figure here is what Keepa held on the day this page was last revised. Offers and prices shift without warning.
Prices quoted in this text were read on October 23, 2026. The live price is at the top of the page.
A listing is not an offer: the reference exists on these stores, availability changes daily.
| Capacity | 1 liter — stated in the title |
|---|---|
| Wall construction | Not published on the listing — the flask is called insulated throughout, and neither a double wall nor a vacuum is named |
| Steel grade | 18/08 stainless steel — stated, and stated to suit carbonated drinks |
| Hot retention | Not published on the listing — 13 hours is published for holding the water temperature stable, without saying whether that is hot, cold or both |
| Cold retention | Not published on the listing — the same single 13 hour figure covers the whole claim, and the listing never separates the two directions |
| Retention conditions stated | Not published on the listing — no starting temperature, ambient temperature or fill level is given behind the 13 hour figure |
| Mouth diameter | Not published on the listing — a bottle brush is supplied, and the opening it goes through is not dimensioned |
| Lid type | Not published on the listing — the flask is stated leak-proof and the closure is never described |
| Seal availability | Not published on the listing — the maker offers a replacement bottle or another solution if the flask leaks, which is a guarantee rather than a spare part |
| Base diameter | Not published on the listing |
| Finish | Not published on the listing |
| Empty weight | Not published on the listing |
| Amazon reference | B08KGPL2GR |
| EAN | 4270001302649 |
The listing does not say. It states the water temperature is held stable for 13 hours and never separates the two. Every other flask here that quotes hours quotes two figures; this one quotes one and leaves its direction open, so this page carries it on neither line as a measurement.
Not that the listing offers. What it does offer is a replacement bottle or another solution if you have leakage problems, plus a 60-day money-back offer. That is a guarantee on the product, not a spare part, and the difference matters on a flask you expect to outlive its first gasket.
No. Not published on the listing — the flask is called insulated throughout, and neither a double wall nor a vacuum is named. What the listing does publish instead is the steel grade: 18/08 stainless steel — stated, and stated to suit carbonated drinks.
8.4/ 10
The flask that ships with the brush and the carabiner, and the one whose insulation claim is the thinnest here: one number, no direction, no construction named.
Close prices, same category: comparable camping gear. We keep only the specifications all of them publish, because a column with gaps compares nothing.
| Model | Price | Capacity | Wall construction | Steel grade | Hot retention |
|---|---|---|---|---|---|
| Blockhütte 1-liter vacuum flask with brush | $33 | 1 liter — stated in the title | Not published on the listing — the flask is called insulated throughout, and neither a double wall nor a vacuum is named | 18/08 stainless steel — stated, and stated to suit carbonated drinks | Not published on the listing — 13 hours is published for holding the water temperature stable, without saying whether that is hot, cold or both |
| Thermos Stainless King SK2000 | $26 | 16 oz — stated, about 470 ml, described as compact. The maker states that the Stainless King also comes in 40 oz and 68 oz. It is the second-smallest capacity in this group | Vacuum insulation — stated as the maker’s own technology, with the exterior stated to stay cool to the touch with hot drinks and sweat-free with cold. No layer count beyond the vacuum | 18/8 stainless steel — stated as high quality, for the body and for the built-in cup | 18 hours — stated twice, in the bullets and in the description. It is the longest hot retention published on this shelf: the other fourteen listings claim 12 hours or less, and one European listing claims 13 hours of stability without separating hot from cold |
| magcheer 1-liter wide-mouth vacuum flask | $22 | 1 liter — stated in the title | Double-wall vacuum insulation — stated | 18/8 stainless steel — stated, described as food grade and non-toxic | 12 hours — stated |
| honogo 32 oz, two lids | $20 | 32 oz — stated, about 950 ml, and stated in both the title and the bullets | Double-layered vacuum insulation — stated, with the bottle described as 100 per cent sweat free and free of condensation | 18/8 of 304 stainless steel — stated, with non-toxic, BPA-free and phthalate-free claims. It is the only listing in this group to give the AISI number behind 18/8; on the European side one listing distinguishes SUS 201 outside from SUS 304 inside | Up to 12 hours — stated, with fresh taste claimed. The common figure on this shelf |
A liter bottle bought with its brush and its carry loop, where cleaning matters more than a comparable hours figure.
Amazon reports what buyers took in the month before this page was last checked: at least 500.
The figure is a floor, rounded by Amazon, and read through Keepa — it says what buyers picked, not what a maker claims.
Specifications: the manufacturer sheet for camping and hiking gear and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.
500 ml · vacuum insulated · SUS 201 outside and SUS 304 inside · 24 h cold and 12 h hot stated · brushed finish · top handle
The only flask here that names a different steel for the inside and the outside, alongside a stated vacuum, both retention figures and a brushed finish.
Best for: A day out where a named inner steel, a stated vacuum and a dishwasher-safe body matter more than the hours quoted.
8 oz · TriMax triple insulation, the only triple-wall claim here · food-grade stainless, grade not named · 24 h stated once, hot and cold not separated · removable 3 oz silicone cup · folding hidden handle · dishwasher safe, flask and cup
The only triple-wall claim on this shelf, on an eight-ounce flask with a removable three-ounce silicone cup in its base — and a single 24-hour figure that does not separate hot from cold.
Best for: A hip-pocket flask for spirits or a single coffee, where two can share from one cup
≈ $10
40 oz · vacuum insulated · food-grade stainless, grade not named · 12 h hot and 24 h cold stated · wide mouth, stated to take ice · straw, chug and handle lids · matte powder coat · twelve dollars
Three lids — straw, twist spout and carry handle — on a forty-ounce wide-mouth bottle with a matte powder coat, for twelve dollars.
Best for: A gym bag and a car boot both, where one bottle has to be a straw bottle, a pour bottle and a carry bottle
≈ $12
