Amazfit Helio Ring: full specs

Re-verification (2026-07-09): the manufacturer source page (us.amazfit.com/products/amazfit-helio-ring) was UNREACHABLE — HTTP 429 on every re-fetch attempt — so its content could not be re-confirmed. All recorded specs were therefore re-verified against the successfully-fetched Amazon US corroboration (ASIN B0D5LPZHLB, Model W2321TY2N, listing "Amazfit Helio Smart Ring"), which confirms EXACT model (standalone Helio Ring, size 12 variant — not the Sizing Kit or a bundle): "Wearable Computer Type Smart Ring" / "Controller Type Ring" (form factor ring); "Water Resistance Depth 100 Meters" (water resistance (m) 100); "Battery Average Life 4 days" (battery days 4); "GPS No GPS" (gps false); "Metrics Measured: Heart Rate Monitor, Sleep Duration, Stress, Blood Oxygen Monitor" plus "blood-oxygen levels" (spo2 true) with NO ECG anywhere in the metrics or spec sheet (ecg false — the device uses an EDA sensor for stress, not ECG); and title "No Subscription" / "without subscriptions" (subscription required false). REMOVED: the price — source page 429-unreachable and Amazon showed only EUR 131.31, so the $149.99 USD figure is not supported by any fetched text. display — left blank; Amazon's auto-populated "Display Type OLED / Screen Size 1.3 Inches / Visible screen diagonal 2 in" fields are spurious and contradicted by the screenless-ring form factor, so any value would be a wrong number. release date and specs.release — no fetched page states any release date or year (Amazon has no "Date First Available" field), so both stay blank. 7 of 9 specKeys survive (>50%) and exact model is confirmed, so publish=true; only the unverifiable price was removed.