Wear the watch. Or the band. Every heartbeat, step, and sleep flows into one app.
Two devices. One stream. No matter how you wear it.
Watch + Band + App: one shared stream
The problem
Every tracker asked you to take something off.
The watch you love. The ring you earned. Your identity.
Stealthy is the first one that asks for nothing.
It disappears into the clasp of the watch you already own,
and starts listening.
Hardware architecture
Ergonomic Engineering. Just Peel and Stick.
After validating over 100 adhesive formulations, the mounting system is built for a 0.25mm flush bond that holds through water, sweat, and daily wear:
- Engineered for versatility, Stealthy mounts securely to most steel bracelets, leather bands, and rubber straps. It is designed to be easily detachable and transferable between timepieces, arriving with six proprietary adhesive strips so you can seamlessly transition it across your curated watch collection.
- Zero Residue: Guarantees 100% clean removability from luxury watch metals without marring.
- Universal Adaptability: Includes 6 spare die-cut mounts (three at 0.25mm, three at 1.1mm) allowing you to effortlessly move your tracker between flat surfaces and complex curved clasps.
- Waterproof & Secure: Engineered to withstand 24/7 wear, sweat, and water.
- Frictionless Application: Effortless to apply and easy to remove when it is time for a change.
Proven metrics
World-class tracking.
Zero wrist presence.
Precise health and activity intelligence, truly invisibly. Continuous monitoring, ultimate comfort. The feed below is an illustration, not measured data.
Heart Rate
live61bpm
Continuous beats-per-minute, resting and active, with zero wrist glow.
HRV
live55ms
Nervous-system balance that powers your focus and recovery scores.
Blood Oxygen
live98%
Night-time and on-demand oxygen-saturation wellness trends.
Sleep Score
live83/100
Light, deep and REM staging with a nightly recharge score on wake.
Stress Load
live22idx
Real-time sympathetic load, mapped against your day so you can act.
The app: iOS & Android
All the metrics.
None of the noise.
Clasp or band: the app stitches both into a single unbroken record of your day. Health, recovery, focus, stress and privacy-first calendar insights in one place.
The app - iOS & Android
All the metrics. None of the noise.
Built for the professional who takes health seriously, demands mental clarity, and refuses to trade a beloved timepiece for another screen.
Health & Recovery
Unbroken 24/7 data continuity
Metrics seamlessly stitch between the clasp and the band so your daily record has no gaps.
Heart rate, HRV & oxygen estimates
Continuous tracking of beats, heart-rate variability, and night-time oxygen-saturation trends for wellness monitoring.
Sleep architecture & recharge
Light, deep and REM stages combined with a nightly recharge score to see how well you recovered.
Daily activity estimates
Steps, distance, calorie burn estimates and Metabolic Equivalent of Task (MET) summaries.
Focus & Cognition
Focus Index & cognitive stamina
Uses HRV and nervous-system signals to highlight your best windows for deep work.
Stress & recovery timeline
Maps daily sympathetic load and recovery states so you can spot patterns over time.
Calendar-aware workload insight
Private calendar sync lets you correlate stress and recovery signals with recurring meetings.
Biological age direction
Estimates a directional biological-age trend using resting heart rate, HRV, and sleep recovery.
Privacy & Hardware
Privacy-first architecture
Local parsing and private .ics imports keep your schedule and behavioural data on your phone.
Multi-device management
Pair, manage and swap between the clasp attachment and standalone sports bands in one profile.
Zero-friction wearability
Low-profile, ergonomic shape built for all-day, all-night comfort so you forget it is gathering data.
Screenless, silent operation
No vibration, no light, no buzz - just continuous background sampling that never interrupts your meeting.
Whether you are wearing the clasp attachment or the sports band, the app keeps a single unbroken record of your day.
The split view
Two lifestyles.
One tracker.
Left / The Watch Enthusiast
Elegance, seamlessly integrated.
For executives, office professionals, and mechanical-watch purists. The clasp attachment enhances the watch you already own, hidden directly beneath the closure assembly, invisible from every angle. No case-back swap, no modification, no compromise to the movement.
- Hidden placement inside the clasp
- No modification to your timepiece
- HRV, resting HR & stress, no screen to distract you
Right / The Active Performer
Unrestricted movement.
For run, gym, swim and sleep. An ergonomic, rugged sports band for the times the watch comes off. Quick-release transition: clasp to sports band in seconds, feeding the same profile, the same history.
- Spare band ships in the box
- Tool-free swap in seconds
- Boardroom and track feed one record
Compatibility & safety
Zero damage to your timepiece.
Adhesive safety proof
The medical-grade adhesive will not trap dirt, will not degrade with sweat, and leaves no micro-scratches on polished precious metals or brushed steel. Removal is clean and residue-free, every time.
Sizing & proportions
The module measures 30mm x 12mm x 4.2mm, slim enough to vanish beneath your clasp without altering how the watch wears or closes.
Strap compatibility
The module works with deployment clasps and metal bracelets, as well as standard pin-buckle / tang leather straps. A flat mounting surface is all it needs.
- Deployment / folding clasps
- Metal bracelets (Oyster & Jubilee style)
- Standard pin-buckle / tang leather straps
Technical specifications
The full spec sheet.
No vague promises. These are the figures the hardware is being validated against.
- Dimensions
- 30mm x 12mm x 4.2mm
- Weight
- 10 to 20 g
- Battery life
- 8 days
- Water resistance
- 3ATM
- Charging
- Magnetic wireless
- Materials
- Resin and stainless steel (watch attachment); zinc alloy and resin (band)
- Offline storage
- Up to 2 days of data without a phone
- Sensors
- PPG, accelerometer, skin temperature
- Connectivity
- Bluetooth [Insert Version]
- Price
- $249 - one-time, no subscription
Specifications apply to both the watch attachment and the sports band. Fields marked [Insert ...] are finalised during the September hardware validation.
Charging
Seamless charging.
Both the watch attachment and the sports band share one battery platform and one charger. Drop either onto the puck and pick it back up topped up.
Watch attachment
1.5 hours
Empty to full on the shared charging puck.
Sports band
2 hours
Empty to full on the same single charger.
Certifications
Certified for both devices.
The watch attachment and the sports band are being validated against the same compliance standards, in every market we ship to.
FCC
United States radio-frequency compliance
CE
European conformity (health, safety, EMC)
RoHS
Restriction of hazardous substances in electronics
Australia RCM
Regulatory Compliance Mark for Australia
Australia CSR
Cyber Security Requirement for connected devices
Certifications are in progress and targeted for both devices ahead of the production run.
Trust & transparency
Built in the open.
About us
A real team, building in Australia.
Stealthy is an officially registered business in Australia (ACN 31 694 833 344). Meet the founders and read about the engineering team behind the hardware.
Read about the teamBacker guarantee & shipping
Your money is protected.
A full refund if September hardware validation fails or the timeline slips. Clear shipping costs, international availability and regional restrictions.
Read the guarantee & shipping FAQTransparent pre-order
Pre-order now to secure your priority delivery from our current manufacturing batch.
Your payment secures a guaranteed delivery from the initial production batch at the final, upfront purchase price of $249. It is a one-time charge no subscription needed.
Late August
CAD & engineering design finalization
Mid-September
Physical sample & hardware validation
October / November 2026
Production run & app beta access
Delivery
Priority shipment to early supporters