Garmin Heart Rate Monitor HRM-Dual

Physical & Performance Battery Life: Approximately 3.5 years (based on average use of 1 hour per day) Battery: User-replaceable size CR2032 (3 volts) Module: 62 mm x 34 mm x 11 mm Operating Temperature -5°C – 50°C Radio Frequency/Protocol: 2.4 GHz ANT wireless communications protocol; BLUETOOTH® Wireless Technology 5.0 Range: 3 m Strap Length: 63.5 cm to 132 cm System Compatibility: ANT+, BLUETOOTH Water Resistance: 1 ATM*(*Does not transmit heart rate data to your device while swimming.) Weight: 54.4 g