Oura - Ring 5 - Smart Ring - Size Before You Buy with OR5 Sizing Kit - Size 11 - Silver - (2026) vs Sr08 Smart Ring Men Women Led Display Screen Heart Rate Blood Oxygen: which is safer?

Oura - Ring 5 - Smart Ring - Size Before You Buy with OR5 Sizing Kit - Size 11 - Silver - (2026) is the clear pick. Sr08 Smart Ring Men Women Led Display Screen Heart Rate Blood Oxygen carries a failing PFAS grade, and we never recommend buying a failing product.

Our pick

Oura - Ring 5 - Smart Ring - Size Before You Buy with OR5 Sizing Kit - Size 11 - Silver - (2026)

Fitbit

Oura - Ring 5 - Smart Ring - Size Before You Buy with OR5 Sizing Kit - Size 11 - Silver - (2026)

PFAS grade

B 85/100

Overall grade

D 67/100

Verdict

Buy

Hazard flags

⚑ 3

Material

Titanium and stainless steel with glass sensor

Confidence

72%

PossibleElectronic component off-gassing or thermal breakdown

ReportedBiofilm and bacterial growth on sensor surfaces

PossibleGlass or metal micro-debris from wear

Why this gradeBuy
Sr08 Smart Ring Men Women Led Display Screen Heart Rate Blood Oxygen

Xiaomi

Sr08 Smart Ring Men Women Led Display Screen Heart Rate Blood Oxygen

PFAS grade

F 40/100

Overall grade

F 24/100

Verdict

Skip

Hazard flags

⚑ 4

Material

Silicone band, metal/plastic housing, unspecified waterproof coating

Confidence

35%

PossibleWaterproof coating composition (unspecified)

PossibleSilicone band degradation over time

PossibleSkin irritation or allergic contact

Why this 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 waterproof smart rings & bands: see the full ranking