T-Rex 3 Pro vs Helio Smart Ring Health Tracker: which is safer?
Amazfit Helio Smart Ring Health Tracker is the clear pick. Amazfit T-Rex 3 Pro carries a failing PFAS grade, and we never recommend buying a failing product.
Amazfit
T-Rex 3 Pro
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleWaterproof coating fluorocarbons (PFAS-class)
PossiblePolymer back-cover off-gassing
PossibleFluoroelastomer strap degradation
Our pick
Amazfit
Helio Smart Ring Health Tracker
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossiblePolymer band composition and residual monomers
PossibleBacterial growth in sealed band-case junction
Where these two actually differ
- We flag Waterproof coating fluorocarbons (PFAS-class), Polymer back-cover off-gassing and Fluoroelastomer strap degradation on the Amazfit and not on the Amazfit.
- We flag Polymer band composition and residual monomers and Bacterial growth in sealed band-case junction on the Amazfit and not on the Amazfit.
- The Amazfit is Stainless steel case, fluoroelastomer strap, polymer back where the Amazfit is Titanium alloy case, polymer band, which is most of the difference in these two grades.
- The gap is 45 points, wide enough that this is not a close call, and the Amazfit is the one to buy.
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 water-resistant smart rings & bands: see the full ranking