Double Wall Vacuum Insulated Stainless Steel Food Canister Container with Leak Proof Lid vs Stainless Steel Bento Box Onyx: which is safer?
Klean Kanteen Double Wall Vacuum Insulated Stainless Steel Food Canister Container with Leak Proof Lid is our pick: better on PFAS and on the overall hazard picture.
Our pick
Klean Kanteen
Double Wall Vacuum Insulated Stainless Steel Food Canister Container with Leak Proof Lid
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleSilicone gasket degradation
PossibleBacterial growth in vacuum seal
PossibleSurface corrosion under acidic conditions
S'well
Stainless Steel Bento Box Onyx
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleSilicone seal degradation
PossibleBacterial or mold growth in seals
Where these two actually differ
- We flag Silicone gasket degradation, Bacterial growth in vacuum seal and Surface corrosion under acidic conditions on the Klean Kanteen and not on the S'well.
- We flag Silicone seal degradation and Bacterial or mold growth in seals on the S'well and not on the Klean Kanteen.
- The Klean Kanteen is Stainless steel body, silicone gasket lid seal where the S'well is stainless steel, silicone seals, which is most of the difference in these two grades.
Both products run through the same public rubric: materials, coatings, brand disclosure, lab findings, and recalls, plus a beyond-PFAS hazard analysis. Grades are model-based estimates, not lab tests. How grades work →
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