Humangear Stax vs Co-op Traverse Modular Bear Canister: which is safer?

Humangear Stax is our pick: better on PFAS and on the overall hazard picture.

Our pick

REI

Humangear Stax

PFAS grade

A 100/100

Overall grade

B 84/100

Verdict

Buy

Hazard flags

⚑ 4

Material

polypropylene plastic

Confidence

72%

PossibleMicroplastic release from mechanical wear

PossibleThermal degradation and chemical leaching at elevated temperatures

PossibleMold and bacterial growth in crevices

Why this gradeBuy

REI

Co-op Traverse Modular Bear Canister

PFAS grade

B 85/100

Overall grade

C 73/100

Verdict

Buy

Hazard flags

⚑ 3

Material

polyethylene plastic construction

Confidence

78%

PossibleMicroplastics from degradation

PossibleMold or bacterial growth inside

PossibleThermal stress and warping

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 waterproof outdoor gear storage: see the full ranking