PSA: Look at the heart rate sensor of your fenix 5. Has it cracks like mine? If yes, it's a common problem. Send it to Garmin and get a free replacement. Do
Garmin fēnix® 5X | Multisport GPS Watch
fēnix 5 Plus Sapphire Ti Gray | スマートウォッチ | Garmin 日本
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Amazon | ガーミン(GARMIN) fenix 5 Plus Sapphire Ti Black 010-01988-84 | ガーミン( GARMIN) | ランニング用GPS・アクセサリ