FreeSip Sway Stainless Steel vs Stainless Steel King Travel Mug: which is safer?
These two grade almost identically. Pick on price and preference; neither has a PFAS edge.
Owala
FreeSip Sway Stainless Steel
PFAS grade
Excellent 80/100
Overall grade
Good 68/100
Verdict
Buy
Hazard flags
⚑ 3
Material
Stainless steel body, no interior coating disclosed
Confidence
87%
PossibleSilicone and plastic lid/valve leachables
PossibleBacterial growth in valve mechanism
PossibleOff-gassing or odor transfer
Thermos
Stainless Steel King Travel Mug
PFAS grade
Excellent 80/100
Overall grade
Good 68/100
Verdict
Buy
Hazard flags
⚑ 3
Material
Stainless steel interior and exterior, plastic lid
Confidence
82%
PossiblePlastic lid polymer degradation
PossibleGasket/seal material composition
PossibleThermal shock stress on seals
Where these two actually differ
- We flag Silicone and plastic lid/valve leachables, Bacterial growth in valve mechanism and Off-gassing or odor transfer on the Owala and not on the Thermos.
- We flag Plastic lid polymer degradation, Gasket/seal material composition and Thermal shock stress on seals on the Thermos and not on the Owala.
- The Owala is Stainless steel body, no interior coating disclosed where the Thermos is Stainless steel interior and exterior, plastic lid, which is most of the difference in these two grades.
- These two are level, close enough that price and fit should decide it rather than our grade.
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 →
More insulated travel mugs: see the full ranking