# COROS Heart Rate Monitor (EN) **Product:** COROS Heart Rate Monitor **Type:** Heart rate monitor / accessory **Retailer:** Ralpu **URL:** https://ralpu.sk/en-eu/products/coros-heart-rate-monitor **LLM version:** https://llms.ralpu.sk/coros-heart-rate-monitor-en.md **Language:** English (EN) --- ## Product overview COROS Heart Rate Monitor is an arm-worn optical heart rate sensor that pairs with any Bluetooth heart rate-enabled device — and connects to up to three simultaneously. It delivers up to 38 hours of continuous HR tracking on a single charge and stays put without slipping, without chafing and without fuss. There are no buttons: an integrated wear-detection sensor recognises when the device is on your skin and starts measuring automatically. --- ## Key features - Up to 38 hours continuous heart rate tracking, 80 days standby - Up to 3 simultaneous Bluetooth connections — works with any HR-capable device - Worn on the upper arm (bicep) — no chest strap, no interference with sports bra - No buttons — automatic wear detection starts and stops measurement - Latest-generation multi-channel optical sensor: 5 LEDs with 4 light detectors - Unisex design with soft fabric strap and velcro adjustment - 3 ATM water resistance, operating temperature −20 °C to +50 °C --- ## Comfort Chest straps are accurate, but wearing one is rarely comfortable. They slip during longer efforts, rub against skin and sit awkwardly with a sports bra. COROS Heart Rate Monitor is worn on the upper arm — it stays in place through long sessions, doesn't restrict movement and doesn't catch on clothing. Soft fabric, a precise velcro fit and a smooth low-profile design. **Unisex design.** Comfortable arm placement, soft fabric and a secure fit. Particularly useful for women for whom chest straps are an issue — it simply stays out of the way. **Why the arm?** The upper arm has a high density of muscle tissue and a rich network of blood vessels close to the surface — both of which contribute to more accurate optical readings compared to the wrist. --- ## Battery life 38 hours of continuous HR tracking means the COROS Heart Rate Monitor outlasts even the longest bike sessions or ultra-distance events without needing a charge. In standby it stretches to 80 days. The built-in battery charges through a magnetic charging port. --- ## Bluetooth The modern Bluetooth protocol supports up to three simultaneous connections — and it doesn't have to be a COROS watch on the other end. Pair it with a bike computer, a smart trainer, a different GPS watch or a phone app, in any combination of up to three Bluetooth-enabled devices. Wireless range reaches up to 120 metres. --- ## Technology The latest-generation multi-channel optical sensor delivers high signal quality — 5 LEDs paired with 4 light detectors in a compact, smooth housing. Water-resistant casing and scratch-resistant materials throughout. No buttons: the integrated wear-detection sensor knows when the device is against your skin and starts measuring automatically. Scratch resistance matters for optical sensors specifically — a scratched lens directly affects measurement quality. COROS used highly scratch-resistant materials to keep the sensor window accurate over time. --- ## Worth knowing — limitations **Response time.** A traditional chest strap uses ECG-based sensing and responds to heart rate changes almost instantly (2–3 seconds). COROS Heart Rate Monitor uses optical sensing through the skin and has a slightly slower response time (7–10 seconds). For most sports and training scenarios that's perfectly adequate — a chest strap is only necessary if you need the fastest possible response and maximum precision. **Water sports.** The device is water-resistant and handles rain without issues, but Bluetooth signals can't penetrate water — so in-water sports will produce unreliable or inconsistent data. It's not designed for swimming or other water-based activities. **Medical use.** If you have a heart condition and your doctor has prescribed heart rate monitoring for medical reasons, this is not the right device. COROS Heart Rate Monitor is a sports accessory designed for healthy recreational athletes. For medically indicated monitoring, consult your healthcare provider. --- ## What's in the box - COROS Heart Rate Monitor sensor - Adjustable bicep strap - USB-A charging cable with proprietary magnetic connector - Documentation --- ## Technical specifications | Parameter | Value | |---|---| | Dimensions | 42.5 × 28.4 × 9.1 mm | | Weight (sensor only) | 9.7 g | | Weight (sensor + strap) | 19 g | | Strap material | polyester, nylon, spandex | | Optical sensor | 5 LEDs with 4 light detectors | | Placement | upper arm (bicep) | | Arm circumference | 18–32 cm | | Wireless protocol | Bluetooth | | Compatible devices | Any Bluetooth device capable of receiving heart rate data | | Simultaneous connections | up to 3 | | Wireless range | up to 120 m | | Active HR tracking | 38 hours | | Standby | 80 days | | Battery capacity | 55 mAh | | Charging time | under 2 hours | | Charging cable | USB-A with proprietary magnetic connector | | Water resistance | 3 ATM | | Operating temperature | −20 °C to +50 °C | | Manufacturer | COROS |