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Mizu M8 with Stainless Steel Cap

Mizu M8 with Stainless Steel Cap

Recommended

Silicone is only a gasket/seal — what touches your food is Stainless Steel (304 / 18-8).

Single-wall 18/8 steel bottle paired with Mizu's all-stainless screw cap, so the water path is steel plus a small silicone gasket.

The verdict: Silicone only

The M8 is a single-wall 18/8 stainless bottle. It ships with a plastic loop cap, but Mizu sells a dedicated all-stainless M-series Steel Cap, and with that cap the water path is 18/8 steel sealed by a small removable silicone gasket - nothing plastic touches the drink. We rate it in that steel-cap configuration; with the stock plastic loop cap it would be minimal-contact. An affordable, widely-sold alternative to the Klean Kanteen / Hydro Flask steel-cap route.

Verification: Manufacturer confirmed · Last reviewed

Requires an upgrade to reach the silicone only rating — you also buy:
Stainless Steel Cap (M-series) · $ Mizu →

The M8 ships with a plastic loop cap; this all-stainless M-series cap is what makes the water path plastic-bar-the-gasket. Buy it separately.

What it's made of

PartMaterialFood contact
bottle body (single-wall)
18/8 (304) food-grade stainless; some finishes add an exterior powder coat that does not contact the drink
Stainless Steel
304 / 18-8
Yes primary
Loop cap (stock - replaced by the Steel Cap) ships with — replace
Plastic loop cap the M8 ships with.
Polypropylene
PP, #5
primary
Steel Cap (add-on - replaces the stock plastic loop cap)
Mizu's all-18/8-stainless M-series cap; a separate SKU.
Stainless Steel
304 / 18-8
Yes primary
cap gasket
small removable silicone sealing gasket - the only non-metal part in the water path
Silicone Yes seal

Mizu's M8 is a lightweight single-wall narrow-mouth 25oz stainless bottle - no insulation, so it's lighter and cheaper than a double-wall bottle. The all-steel M-series cap it takes fits every M-series body (M5, M8), so one cap covers the range. It's the affordable end of the "steel body + steel cap" route that Klean Kanteen and Hydro Flask also sell.

Pros

  • Among the cheapest ways into an all-steel drink path
  • One cap fits the whole M-series line (M5, M8)
  • Light single-wall body; the silicone gasket is small and removable

Cons

  • Doesn't ship this way - the all-stainless cap is a separate purchase
  • Single-wall, so no insulation
  • Some finishes use an exterior powder coat (doesn't touch the drink, but worth noting)
  • The all-steel cap has been intermittently backordered

Notes

Categories: Water Bottles

Sources

Every material claim above is backed by these. This is the scattered info we centralized.

Spot a mistake or something out of date? Let us know — corrections are how this stays accurate.