Amazfit T-Rex Ultra 2 / Samsung Galaxy Watch5 Pro (45 mm)

Amazfit T-Rex Ultra 2: A2550 · 51 mm · Black Magma · silicone strap

Samsung Galaxy Watch5 Pro (45 mm): The Galaxy Watch5 Pro comes in one size (45 mm): SM-R920 (Bluetooth) and SM-R925 (LTE), in Black Titanium and Gray Titanium. The 40/44 mm Galaxy Watch5 is a separate model with a different battery, case material and display size.

SpecificationAmazfit T-Rex Ultra 2Samsung Galaxy Watch5 Pro (45 mm)
Release year20262022
Announcement / availability19 February 2026 Amazfit—
Display1.5-inch AMOLED · 480 × 480 · sapphire glass Amazfit1.4-inch (34.6 mm) 450 × 450 Super AMOLED; full-colour Always On Display

The bezel is raised above the display, which Samsung designs to protect the glass from knocks. There is no rotating bezel; menus are navigated with touch gestures and the buttons.

Samsung
Peak brightnessUp to 3000 nits

With auto brightness; unavailable in low-temperature mode or below 30% battery.

Amazfit
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BodyPolymer case; Grade 5 titanium bezel, buttons and back Amazfit—
Size / weight51 × 51 × 14.3 mm; 89.2 g with strap

Thickness excludes heart-rate sensor base.

Amazfit
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Strap26 mm silicone; 145–215 mm wrist Amazfit—
Storage64 GB total; up to 26.7 GB user space Amazfit—
PositioningDual-band GNSS; six satellite systems Amazfit—
SensorsBioTracker 6.0 PPG; barometer, compass, motion and temperature sensors AmazfitSamsung BioActive Sensor (Optical Heart Rate + Electrical Heart Signal + Bioelectrical Impedance Analysis), temperature, accelerometer, barometer, gyro, geomagnetic, light sensor

Electrical Heart Signal enables ECG and Bioelectrical Impedance enables body composition estimates; ECG works through the Samsung Health Monitor app only in approved markets.

Samsung
Battery870 mAh; up to 30 typical / 15 heavy / 10 AOD days

Separate manufacturer scenarios, not continuous GPS endurance.

Amazfit
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GPS battery modesUp to 50 Accurate / 90 saving / 177 max-battery hours Amazfit—
WirelessBluetooth 5.2 BLE; 2.4 GHz Wi-Fi Amazfit—
Water / diving10 ATM; recreational diving up to 45 m

Not for technical, cave or mixed-gas diving.

Amazfit
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Phone connectionAndroid 7+ / iOS 15+; Zepp app Amazfit—
ChargingMagnetic charging puck; USB-C cable separate Amazfit—
CallsBluetooth calls using microphone/speaker Amazfit—
Glass and case—Sapphire Crystal; titanium case with D-Buckle Sport Band

The D-buckle band folds open; because the watch cannot lie flat, it is charged on its side on the Samsung charger.

Samsung
Processor—Exynos W920, dual-core 1.18 GHz Samsung
Memory and storage—1.5 GB RAM + 16 GB internal storage Samsung
Battery and charging—590 mAh (typical); WPC-based wireless faster charging

Samsung says real battery life varies with network environment and usage patterns. 590 mAh is about 44% larger than the 410 mAh battery in the 44 mm Galaxy Watch5.

Samsung
Operating system—Wear OS 3.5 (Powered by Samsung) with One UI Watch 4.5 at launch

Activation requires connecting to an Android phone with Google Mobile Services; it cannot be used with an iPhone.

Samsung
Connectivity—Bluetooth 5.2, Wi‑Fi 802.11 a/b/g/n 2.4 + 5 GHz, NFC, GPS/Glonass/Beidou/Galileo; LTE (LTE model only)

The LTE model can make calls and use data without the phone nearby; support depends on the carrier.

Samsung
Durability—5ATM + IP68 / MIL-STD-810H

5ATM covers surface water use such as swimming, not diving or high-pressure water. MIL-STD-810H is the US military standard for environmental test methods.

Samsung
Phone compatibility—Android 8.0 or higher with more than 1.5 GB of RAM Samsung
Size and weight—45.4 × 45.4 × 10.5 mm; 46.5 g

Dimensions are measured without the health sensors and weight without the strap.

Samsung