40/ 100
F
OverallF24/100
Sr08 Smart Ring Men Women Led Display Screen Heart Rate Blood Oxygen

Xiaomi · Waterproof Smart Rings & Bands

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

F · High PFAS

Waterproof wearable with unspecified coating; insufficient PFAS transparency.

Verdict: SkipSilicone wearable with unspecified waterproof coating and PFAS uncertainty; low acute risk but transparency gaps warrant cautious use and regular inspection.

Smart rings typically use waterproof treatments that may contain PFAS. Xiaomi provides no public PFAS disclosure for this model. Limited data available for confident assessment.

The safe swap

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)

85/100 safety

B

Still want this one anyway? Check the price on Amazon. We’d swap it.

Material

Silicone band, metal/plastic housing, unspecified waterproof coating

Brand disclosure

Brand is silent on PFAS

Lab data

No public lab test

Why this grade

Waterproof / stain-resistant treatment

water-repellent coating treatments have historically used PFAS.

Hurts the grade

Category baseline

other is a category where PFAS exposure is more common.

Hurts the grade

No PFAS disclosure

No public statement about PFAS in this product.

Hurts the grade

The full breakdown

What it's made of and why it matters

The Sr08 combines a silicone elastomer band with a plastic and metal (likely stainless steel or aluminum alloy) housing. The silicone band itself is generally regarded as low-toxicity and food-contact safe under normal conditions, but the waterproof coating and adhesives binding the band to the housing are not specified by Xiaomi. Waterproof coatings on wearables often contain Teflon-family coating or other water-repellent compounds; without disclosure, PFAS risk cannot be ruled out. The metal housing and any internal battery connections pose minimal leaching risk if the coating remains intact.

The brand's record and disclosure

Xiaomi does not publicly disclose material safety data sheets, PFAS content, or third-party certifications for most wearables, including the Sr08. The company has faced no major recalls or established safety controversies for this specific model, but the lack of transparency on waterproof chemistry is notable. Xiaomi's consumer wearables operate in a regulatory gray zone where full material disclosure is not mandated in most markets. This silence does not indicate a problem, but it does limit independent verification.

How it compares in its category

Smart rings and fitness bands are among the least regulated wearable categories; most competitors (Oura, Apple Watch, Fitbit) also avoid detailed coating disclosures, making the Sr08 typical rather than exceptional. Silicone bands are standard across the category and generally preferred over thermoplastic rubber or leather for durability and skin contact. The Sr08's main differentiator is price, not material safety; mid-range wearables of this type rarely undergo third-party toxicology testing or publish results. Compared to budget alternatives, Xiaomi's manufacturing standards are generally considered reliable.

If you buy it

Store and charge in a cool, dry place; avoid prolonged exposure to direct sunlight or heat above 50°C, which may accelerate degradation of the silicone or coating. Inspect the band weekly for cracks, peeling, or discoloration, especially at seams where water may penetrate. Rinse with fresh water after sweat or saltwater exposure and allow to air dry completely before wearing again. Replace the band or the device if the coating shows visible wear or if skin irritation develops, though silicone itself is a low-allergen material.

Beyond PFAS: other things we checked

Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”

Possible

Waterproof coating composition (unspecified)

The Sr08's waterproof treatment is not disclosed; coatings may contain Teflon-family coating, siloxanes, or other persistent compounds. No recall or test data on record, but lack of transparency prevents full hazard assessment.

Possible

Silicone band degradation over time

Extended UV exposure or high heat can cause silicone to become brittle or leach oligomers. Risk is low under normal use, but daily sunlight and sweat exposure may accelerate this over 1-2 years.

Possible

Skin irritation or allergic contact

Silicone is generally hypoallergenic, but residual monomers, release agents, or adhesives in the band-to-housing joint could trigger localized dermatitis in sensitive individuals. Incidence is not tracked for this model.

None known

Heavy metals in electronic components

The metal housing and internal circuitry are typically compliant with RoHS and WEEE standards in most markets where Xiaomi sells, limiting lead, cadmium, and mercury risk. No specific testing data published for this model.

Possible

Battery or electronic fluid leakage

Crack or puncture to the housing could expose internal battery or electrolyte; risk is low if the device is not dropped or crushed, but the waterproof seal's durability is unverified.

What we don’t know

This grade is a model-based estimate from public materials, coatings, and brand disclosure at 35% confidence. It is not a lab result.

No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.

The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.

Formulations and coatings change between production runs. Always check the current label before buying.

Safer alternatives in Waterproof Smart Rings & Bands

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)

Titanium and stainless steel with glass sensor

B
D
PFASAll
B · Low PFAS3 flags

Lower concern smart ring; no PFAS-prone materials identified.

Brand says nothing about PFAS

Qalo QRNT Slim Smart Ring

Fitbit

Qalo QRNT Slim Smart Ring

silicone elastomer with metal core

B
D
PFASAll
B · Low PFAS3 flags

Smart ring with silicone body; lower concern but no public PFAS disclosure.

Brand says nothing about PFAS

Withings Black Smart Ring Size 9 - New Women | Color: Black

Withings

Black Smart Ring Size 9 - New Women | Color: Black

Titanium alloy ring with sapphire crystal display

B
D
PFASAll
B · Low PFAS3 flags

Lower concern. Smart ring materials inherently unlikely to require PFAS.

Brand says nothing about PFAS

More waterproof smart rings & bands grades

How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.