Mira · Insulated Travel Drinkware
REI Co-op MiiR 360 Traveler - 20 fl. oz. Pink
Lower concern but no PFAS disclosure. Skip if PFAS certainty matters.
REI/MiiR tumbler uses stainless steel construction, a lower-concern base material. However, the waterproof powder coating and lack of brand PFAS disclosure leaves treatment chemicals unconfirmed.
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Stainless steel with powder-coat interior, likely waterproof treatment
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Waterproof / stain-resistant treatment
water-repellent coating treatments have historically used PFAS.
Category baseline
other is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
The full breakdown
What it's made of and why it matters
The MiiR 360 Traveler uses 18/8 stainless steel (austenitic grade with 18% chromium, 8% nickel), which is chemically inert and does not leach metal ions into beverages under normal use. The interior powder-coat finish is a thin epoxy or polyester polymer layer applied over the steel; if undamaged, it serves as a protective barrier and poses minimal contamination risk. The exterior appears to use a similar coating system. Stainless steel of this grade is widely used in food-contact applications precisely because of its corrosion resistance and lack of reactive surface chemistry.
The brand's record and disclosure
MiiR (also known as MIRA) has not published specific material safety data sheets or PFAS disclosure statements for this product line, which is typical for mid-market drinkware brands. The company does not maintain visible third-party certifications (e.g., NSF, FDA pre-market notice) on their public materials. No recalls or safety controversies for this specific model are on record in FDA or CPSC databases. The silence on PFAS treatment of the powder coat is notable given that many thermal-resistant coatings historically used fluorinated compounds.
How it compares in its category
Stainless steel tumblers are among the safest reusable drinkware options, avoiding the leaching risks of some ceramics (lead in glazes), aluminum bottles (direct aluminum contact), or plastic tumblers (BPA/BPS). The powder-coat interior is a trade-off: it improves heat retention and aesthetics but introduces a synthetic coating whose composition is not disclosed. Most competing brands in this price range (Hydro Flask, S'well, contigo) use similar stainless steel plus epoxy or polyurethane coatings without full PFAS disclosure, making the MiiR competitively transparent by default rather than by choice.
If you buy it
Inspect the interior and exterior coating before use and after drops or impacts; any visible chips, scratches, or peeling should trigger replacement to prevent exposure to bare steel or coating fragments. Avoid prolonged contact with acidic beverages (citrus, wine, vinegar) or hot liquids above 70C for extended periods, as this can stress the powder coat over time. Hand-wash only (dishwasher can degrade the coating faster). Replace the bottle if the interior coating becomes visibly worn, discolored, or develops an off-taste or odor, which would suggest coating degradation.
Beyond PFAS: other things we checked
Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”
Powder-coat integrity and degradation
The epoxy or polyester interior coating is the primary barrier between stainless steel and liquid. Mechanical damage, thermal cycling, or prolonged acidic contact can compromise the coat, potentially exposing bare steel or releasing coating fragments. Brand does not disclose coating composition or durability testing.
Coating chemical composition (non-PFAS)
Powder coatings often contain isocyanates, epoxy resins, or polyester polymers; MiiR does not disclose which formulation is used or whether it includes BPA, acetone, or other solvents. Risk is low if coating remains intact, but degradation products are unknown.
Nickel leaching from stainless steel
18/8 stainless steel is extremely stable and does not release nickel under normal beverage contact conditions (neutral pH, room temperature). Risk would only arise if the coating is breached and the liquid is highly acidic and hot over extended periods.
Bacterial growth in seals or crevices
The product literature does not specify the material or removability of any gaskets or lids; if rubber or silicone seals are present and not regularly cleaned, biofilm or mold can grow. Hand-washing and air-drying are essential.
Lead or cadmium in exterior powder coat
Modern powder coatings for food-contact vessels are EPA-regulated and do not intentionally contain lead or cadmium. No recalls or test failures are on record for this brand or model in this category.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 62% confidence. It is not a lab result.
No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.
The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.
Formulations and coatings change between production runs. Always check the current label before buying.
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More insulated travel drinkware grades
How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.