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Amazfit T-Rex 3 vs Garmin Forerunner 165
The specs that matter for triathlon, side by side, from each maker’s own published figures.
| Spec | Amazfit T-Rex 3 | Garmin Forerunner 165 |
|---|---|---|
| GPS battery | 42 h | 19 h |
| Smartwatch battery | 27 days | 11 days |
| Triathlon / multisport mode | Yes | No |
| Onboard maps | Yes | No |
| Open-water GPS (our rating) | 5 / 5 | 3 / 5 |
| Weight | 68.3 g | 39 g |
| Screen | AMOLED | AMOLED |
Open-water GPS is our 1–5 rating from the satellite systems each maker lists: multi-band receivers score 5. Everything else is the maker’s own figure.
Which should you pick?
Amazfit
Pick the T-Rex 3 if…
- you want the longer GPS battery: 42 h vs 19 h
- you want the longer smartwatch battery: 27 days vs 11 days
- you want a triathlon (multisport) mode
- you want onboard maps
- you want better open-water GPS (our rating): 5 / 5 vs 3 / 5
Specs from the makers’ own pages: Amazfit, Garmin.
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