Cold Tumbler vs Insulated TKWide Cap: 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

Why this gradeBuy

Klean Kanteen

Insulated TKWide Cap

PFAS grade

B 85/100

Overall grade

C 73/100

Verdict

Buy

Hazard flags

⚑ 3

Material

Stainless steel bottle, plastic cap and silicone gasket

Confidence

78%

PossibleSilicone gasket degradation and leachables

PossibleBacterial or mold growth in cap assembly

PossibleCap or gasket failure under temperature stress

Why this gradeBuy

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