Fitbit · Waterproof Smartwatch Bands
StrapsCo Slim Active Band for Fitbit Sense
Skip until Fitbit discloses waterproofing chemistry.
Fitbit does not publicly disclose whether this elastomer band uses PFAS-based water-resistant treatments. Sportswear bands commonly employ water-repellent coating coatings that may contain PFAS, but specific formulation is undisclosed.
The safe swap
Timex
Timex 12-16mm Hook & Loop Fast Wrap Replacement Watch Band Strap Adult
85/100 safety
Still want this one anyway? Check the price on Amazon. We’d swap it.
Material
Elastomer band with water-resistant treatment
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.
Category baseline
other is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
The full breakdown
What it's made of and why it matters
StrapsCo Slim Active Band is an elastomer (synthetic rubber) strap with an unspecified water-resistant surface treatment. Elastomers are generally stable and non-leaching during normal wear, but the coating chemistry that makes it water-resistant is the critical unknown. Fitbit has not publicly identified whether this uses Teflon-type coating (Teflon-class Teflon-family coating), paraffin wax, silicone oils, or other hydrophobic agents. The proprietary nature of this coating is the primary safety concern.
The brand's record and disclosure
Fitbit (owned by Google since 2021) has not issued public statements about PFAS-free manufacturing or waterproofing chemistry for wearable bands. The company does not list material certifications (Oeko-Tex, GOTS) or restricted substance lists for accessories on their product pages. No recalls or safety incidents specific to StrapsCo bands have been documented in public safety databases. This silence on fluorochemical use is consistent with the broader wearables industry, where waterproofing ingredients remain largely proprietary.
How it compares in its category
Fitbit bands are mid-market for wearable straps; most competing smartwatch bands (Apple, Samsung, Garmin) similarly lack transparency on waterproofing additives. Third-party elastomer bands often use identical unspecified coating treatments. Some premium alternatives (e.g., Patagonia-partnered or sports-specific bands) explicitly state PFAS-free status or use mechanical water barriers instead of chemical coatings. The Slim Active Band offers no differentiation in safety disclosure.
If you buy it
Rinse the band with fresh water after saltwater or chlorine exposure to minimize any potential leaching of coating compounds into skin. Replace the band every 12-18 months, especially if the surface coating visibly degrades, cracks, or peels. Do not expose to extreme heat (above 50°C / 122°F) as this may compromise coating integrity. Store in a cool, dry place when not in use to slow degradation of the elastomer 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.”
Undisclosed fluorochemical waterproofing (PFAS-class)
Fitbit has not disclosed the chemical identity of the water-resistant coating on this band. Industry-standard Teflon-family coating or other fluorinated compounds cannot be ruled out, though direct skin contact risk is lower than ingestion. See PFAS verdict above.
Coating degradation and microparticle shedding
Elastomer surface coatings degrade over time with sweat, UV exposure, and flexing. Microscopic particles of the worn coating may be shed onto skin; composition and safety of these particles are unknown without ingredient disclosure.
Skin irritation from synthetic rubber or additives
No documented cases of allergic reaction or dermatitis from StrapsCo bands; elastomers are widely used in medical devices and generally well-tolerated. Individuals with latex sensitivity should check product specifications, though most modern elastomers are latex-free.
Heavy metals in colorants or pigments
No recalls or test data indicate heavy metal contamination in Fitbit band dyes. Elastomer colorants used in consumer wearables are typically compliant with EU RoHS standards, though formal certification is not published for this product.
Adhesive or bonding agent toxicity
The band's connection to the watch case involves adhesives and/or mechanical fastening. No public information on adhesive composition or off-gassing has been reported for Fitbit bands, suggesting either safety or industry-wide opacity.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 45% 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 Smartwatch Bands
Timex
12-16mm Hook & Loop Fast Wrap Replacement Watch Band Strap Adult
Fabric strap with hook and loop fasteners
Lower concern fabric watch band, no high-risk treatment indicators documented.
⚠Brand says nothing about PFAS
Timex
Rubber watchband for TIMEX watch T2N720 TW2T76300 T2N721 Series Men
Rubber (elastomer, uncoated)
Lower concern. Bare rubber unlikely to contain PFAS intentionally.
⚠Brand says nothing about PFAS
Timex
T77601 Expedition Leather and Canvas Watch Strap (18mm)
leather and canvas
Lower concern. Leather and canvas unlikely to contain PFAS.
⚠Brand says nothing about PFAS
More waterproof smartwatch 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.