Garmin Approach® S40 vs Garmin D2™ AirSize, Specs & Wrist Fit Compared
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Garmin
Approach® S40 (010-02140-02)
Garmin
D2™ Air (010-02173-41)
The Garmin Approach® S40 and Garmin D2™ Air share a near-identical 43.4mm case, so wrist presence comes down to thickness, lug-to-lug and weight.
The Garmin Approach® S40 is the slimmer of the two (11.7mm vs 12.4mm), so it slides under a cuff more easily.
On the wrist the Garmin Approach® S40 feels lighter (43g vs 46.3g, case only).
Specification Comparison
| Spec | GarminApproach® S40 | GarminD2™ Air |
|---|---|---|
| Case Width | 43.4mm | 43.2mm |
| Thickness | 11.7mm | 12.4mm |
| Weight | 43g | 46.3g |
| Shape | Circular | Circular |
| GPS | Yes | Yes |
| Battery life | Smartwatch mode: Up to 10 daysGPS mode: Up to 15 hours | Smartwatch mode: Up to 5 days GPS mode with music: Up to 6 hours GPS mode without music: Up to 20 hours GPS+SPO2: Up to 10 hours |
| Body Battery™ energy monitor | — | Yes |
Full Specification Comparison
145 specs| Spec | Garmin Approach® S40 | Garmin D2™ Air |
|---|---|---|
| Overview | ||
| Family | Garmin | Garmin |
| General | ||
| Battery life | Smartwatch mode: Up to 10 daysGPS mode: Up to 15 hours | Smartwatch mode: Up to 5 days GPS mode with music: Up to 6 hours GPS mode without music: Up to 20 hours GPS+SPO2: Up to 10 hours |
| Display Size | 1.2 in (30.4mm) diameter | 1.2" (30.4mm) diameter |
| Color display | Yes | Yes |
| Lens Material | chemically strengthened glass | Corning® Gorilla® Glass 3 |
| Bezel Material | metal | stainless steel |
| Memory/History | 64 MB | 7 timed activities, 14 days of activity tracking data |
| Strap material | silicone | silicone and leather |
| Charging method | Garmin proprietary plug charger | Garmin proprietary plug charger |
| Display resolution | 240 x 240 pixels | 390 x 390 pixels |
| Quick Release bands | Yes | yes (20 mm, Industry standard) |
| Case material | — | fiber-reinforced polymer with polymer rear cover |
| Sensors | ||
| GPS | Yes | Yes |
| Gyroscope | Yes | Yes |
| Accelerometer | Yes | Yes |
| Compass | — | Yes |
| GLONASS | — | Yes |
| Galileo | — | Yes |
| Thermometer | — | yes (tempe™ sensor required) |
| Ambient light sensor | — | Yes |
| Barometric altimeter | — | Yes |
| Pulse Ox Blood Oxygen Saturation Monitor | — | Yes |
| Garmin Elevate™ wrist heart rate monitor | — | Yes |
| Product Info | ||
| Main SKU | 010-02140-02 | 010-02173-41 |
| Product ID | 635923 | 707506 |
| Product Name | Approach® S40 | D2™ Air |
| Product Variation | Light Gold with White Band | GPS Smartwatch for Aviators |
| Clock Features | ||
| Timer | Yes | Yes |
| Stopwatch | Yes | Yes |
| Time/date | Yes | Yes |
| Alarm clock | Yes | Yes |
| GPS Time Sync | Yes | Yes |
| Sunrise/sunset times | Yes | Yes |
| Automatic daylight saving time | Yes | Yes |
| Golfing Features | ||
| Custom targets | Yes | — |
| Handicap scoring | Yes | — |
| Digital scorecard | Yes | Yes |
| Garmin AutoShot™ | Yes | Yes |
| Round timer/odometer | Yes | Yes |
| TruSwing™ compatible | Yes | — |
| Auto CourseView updates | Yes | — |
| Yardage to layups/doglegs | Yes | Yes |
| Hazards and course targets | Yes | Yes |
| Green View with manual pin position | Yes | Yes |
| Preloaded with 43,000 courses worldwide | Yes | — |
| CT10 Automatic club tracking compatible (requires accessory) | Yes | Yes |
| Yardage to F/M/B (distance to front, middle and back of green) | Yes | Yes |
| Stat tracking (strokes, putts per round, greens and fairways hit) | Yes | Yes |
| Measures shot distance (calculates exact yardage for shots from anywhere on course) | automatic | automatic |
| PinPointer | — | Yes |
| Tournament legal | — | Yes |
| Pairs with Garmin Golf app | — | Yes |
| Running Features | ||
| GPS-based distance, time and pace | Yes | Yes |
| Run workouts | — | Yes |
| Foot pod capable | — | Yes |
| Cadence (provides real-time number of steps per minute) | — | Yes |
| Activity Profiles | ||
| Cycling | Biking, Indoor Biking | Biking, Indoor Biking |
| Gym | — | Strength, Cardio and Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Breathwork, Pilates, Yoga |
| Swim | — | Pool Swimming |
| Outdoor recreation | — | Skiing, Snowboarding, XC Classic Skiing, Stand Up Paddleboarding, Rowing |
| Daily Smart Features | ||
| Calendar | Yes | Yes |
| Connectivity | Bluetooth® Smart | Bluetooth®, ANT+®, Wi-Fi® |
| Find My Phone | Yes | Yes |
| Weather forecasts | Yes | Yes |
| Smart Notifications | Yes | Yes |
| Smartphone compatibility | iPhone®, Android™ | iPhone®, Android™ |
| Pairs with Garmin Connect™ Mobile | Yes | Yes |
| Find My Watch | — | Yes |
| Controls smartphone music | — | Yes |
| Plays and controls watch music | — | Yes |
| Text response/reject phone call with text (Android™ only) | — | Yes |
| Connect IQ™ (downloadable watch faces, data fields and apps) | — | Yes |
| Activity Tracking Features | ||
| TrueUp™ | Yes | Yes |
| Step counter | Yes | Yes |
| Move alerts (displays on device after a period of inactivity) | Yes | Yes |
| Auto goal (learns your activity level and assigns a daily step goal) | Yes | Yes |
| Move IQ™ | — | Yes |
| Floors climbed | — | Yes |
| Calories burned | — | Yes |
| Distance traveled | — | Yes |
| Intensity minutes | — | Yes |
| Automatic rep counting | — | Yes |
| Garmin Connect™ Challenges app | — | yes (optional Connect IQ app) |
| Health & Wellness Monitoring | ||
| Hydration | yes (in Garmin Connect™) | Yes |
| Women's health | yes (in Garmin Connect™) | Yes |
| Sleep | — | yes (advanced) |
| Fitness age | — | yes (in app) |
| All-day stress | — | Yes |
| Respiration rate | — | Yes |
| Resting heart rate | — | Yes |
| Relaxation reminders | — | Yes |
| Abnormal heart rate alerts | — | yes (high and low) |
| Relaxation breathing timer | — | Yes |
| Body Battery™ energy monitor | — | Yes |
| Wrist-based heart rate (constant, every second) | — | Yes |
| Training, Planning and Analysis Features | ||
| GPS speed and distance | Yes | Yes |
| Touch and/or button lock | Yes | Yes |
| Auto Pause® automatic timer halt | Yes | Yes |
| Auto Lap® interval tracking feature | Yes | Yes |
| % HR max | — | Yes |
| HR zones | — | Yes |
| HR alerts | — | Yes |
| Manual lap | — | Yes |
| Auto scroll | — | Yes |
| HR calories | — | Yes |
| Physio TrueUp | — | Yes |
| VO2 Max (Run) | — | Yes |
| Advanced workouts | — | Yes |
| Customizable data pages | — | Yes |
| Activity history on watch | — | Yes |
| Downloadable training plans | — | Yes |
| Customizable activity profiles | — | Yes |
| Respiration rate (during exercise) | — | Yoga and Breathwork only |
| HR broadcast (broadcasts HR data over ANT+® to paired devices) | — | Yes |
| Cycling Features | ||
| Compatible with Varia™ lights | — | Yes |
| Speed and cadence sensor support (w/sensor) | — | Yes |
| Compatible with Varia™ radar (rear-facing radar) | — | Yes |
| Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories) | — | Yes |
| What You'll Love | ||
| Garmin Pay™ | — | Yes |
| Pulse Ox blood oxygen | — | yes (spot-check, and optionally all-day and in sleep) |
| Aviation Features | ||
| In-flight Pulse Ox | — | Yes |
| Waypoint information page | — | Yes |
| Worldwide airport database(s) | — | Yes |
| Multiple time zones with Zulu/UTC | — | Yes |
| TAF (Terminal Aerodrome Forecast) | — | Yes |
| Altimeter with adjustable baro setting | — | Yes |
| METAR (Meteorological Aerodrome Report) | — | Yes |
| Worldwide NAVAID and Intersection database(s) | — | Yes |
| Wirelessly receive flight plans from Garmin Pilot™ | — | Yes |
| 3-axis compass with HSI (horizontal situation indicator) | — | Yes |
| Swimming Features | ||
| Time and distance alerts | — | Yes |
| Underwater wrist-based heart rate | — | Yes |
| Basic rest timer (up from 0) (pool swim only) | — | Yes |
| Stroke type detection (freestyle, backstroke, breaststroke, butterfly) (pool swim only) | — | Yes |
| Pool swim metrics (lengths, distance, pace, stroke count, swim efficiency (SWOLF), calories) | — | Yes |
| Outdoor Recreation | ||
| Back to start | — | Yes |
| Total ascent/descent | — | Yes |
| Workout and Training Plans | ||
| Yoga workouts | — | Yes |
| Cardio workouts | — | Yes |
| Pilates workouts | — | Yes |
| Strength workouts | — | Yes |
| On-screen workout animations | — | Yes |
| Safety and Tracking Features | ||
| Assistance | — | Yes |
| Incident Detection during select activities | — | Yes |
| Kid Activity Tracking Features | ||
| Toe-to-Toe™ Challenges app | — | yes (optional Connect IQ Toe-to-Toe™ Challenges app) |
Wrist Fit
Garmin Approach® S40
Sits best on wrists ~46–62mm wide (≈ 12.3–16.6cm circumference).
Garmin D2™ Air
Sits best on wrists ~45–62mm wide (≈ 12.0–16.6cm circumference).
2D Dimension Schematics
Accurate scale drawings based on case dimensions. Drag to pan, Ctrl+scroll to zoom. Works for every watch regardless of photo availability.
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Frequently Asked Questions
Is the Garmin Approach® S40 bigger than the Garmin D2™ Air?
The Garmin Approach® S40 is bigger — 43.4mm vs 43.2mm case width.
Which fits a smaller wrist better, the Garmin Approach® S40 or the Garmin D2™ Air?
The Garmin Approach® S40 suits wrists around 46–62mm wide, and the Garmin D2™ Air around 45–62mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Garmin Approach® S40 and Garmin D2™ Air side by side at true scale?
Yes — the schematics and photos above show both watches at matched scale, and our fit tool overlays each on your wrist width.