Cold Tumbler vs Tumblers - Set of 4: which is safer?
Ember Cold Tumbler is our pick: better on PFAS and on the overall hazard picture.
Our pick
Ember
Cold Tumbler
PFAS grade
A 100/100
Overall grade
A 92/100
Verdict
Buy
Hazard flags
⚑ 2
Material
stainless steel with silicone seal
Confidence
72%
PossibleSilicone seal degradation and microbial growth
PossibleCoatings or adhesives on printed logos
Ember
Tumblers - Set of 4
PFAS grade
A 100/100
Overall grade
B 88/100
Verdict
Buy
Hazard flags
⚑ 3
Material
Stainless steel double-wall insulated
Confidence
72%
PossibleDouble-wall separation and structural failure
PossibleLid seals and gasket materials
PossibleNickel sensitivity from stainless steel contact
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 drinkware: see the full ranking