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Black optical heart-rate sensor on adjustable armband, matte ABS shell, magnetic charging cable included

HTC HW401 Optical Heart Rate Armband wearable technology

SKU CH-RP4J-3GQCV

An optical heart-rate armband with IP67 water resistance, Bluetooth and ANT+ connectivity, and a rechargeable battery lasting 20 hours

  • ColorBlack
  • TypeSmart Watch
  • SizeLarge
  • OS CompatibilityWindows
  • SensorsOptical Heart Rate Sensor x 1
  • Screen Size1.04"
  • Precise heart-rate tracking with optical sensor accuracy up to ±1 bpm
  • Bluetooth and ANT+ dual mode connects to fitness apps and equipment
  • IP67 waterproof rating resists sweat and water during most sports
  • Rechargeable battery delivers 20 hours continuous use per charge
  • Light breathable adjustable armband fits comfortably for extended training sessions

HTC HW401 Optical Heart Rate Armband

The HTC HW401 is an optical heart rate sensor worn on the arm and designed for athletes who want precise, real-time data during training. It pairs with popular fitness apps and equipment using Bluetooth and ANT+ dual-mode connectivity. The adjustable strap fits a wide range of arm sizes for secure, comfortable wear. It is not suited for swimmers or users who need on-device storage for offline workouts.

IP67 Waterproof Rating and 20-Hour Battery

The unit carries an IP67 rating, protecting it against sweat and rain during outdoor or indoor sessions, though it is not rated for swimming. A 90 mAh rechargeable lithium battery delivers up to 20 hours of continuous operation on a single magnetic charge. LED indicators flash blue during pairing and heart rate acquisition, then slow to a steady pulse once locked. A red flash signals shutdown, giving clear status feedback without a display.

Upgrade from Chest Straps or Basic Trackers

This armband replaces uncomfortable chest straps and less accurate wrist-based trackers for runners, cyclists and gym users who value ±1 bpm precision. The jump is worth it when you need reliable heart rate and step data streamed live to platforms like Zwift, Wahoo Fitness or Elite HRV. It does not measure HRV or store workouts internally, so users who require heart-rate variability analysis or phone-free recording should look elsewhere.

Highlights

  • Precise heart-rate tracking with optical sensor accuracy up to ±1 bpm
  • Bluetooth and ANT+ dual mode connects to fitness apps and equipment
  • IP67 waterproof rating resists sweat and water during most sports
  • Rechargeable battery delivers 20 hours continuous use per charge
  • Light breathable adjustable armband fits comfortably for extended training sessions

Specifications

BrandHTC
ModelHW401
ColorBlack
TypeSmart Watch
SizeLarge
OS CompatibilityWindows
SensorsOptical Heart Rate Sensor x 1
Screen Size1.04"
Operating Time20 hours
Standby Time20 hours
Specificationmoofit, 20 hours, lithium_ion, 0, Acrylonitrile Butadiene Styrene (ABS), Optical Heart Rate Sensor x 1
FeaturesHeart Rate Monitor
Package ContentOptical Heart Rate Sensor x 1, Armband x 1, Charging Cable x 1, Getting Started Guide x 1

Questions about this item

How do I install the HW401 armband so the sensor stays in place during training?

Wrap the 380 mm adjustable strap around your upper arm with the optical sensor flat against the skin, then tighten until the band feels secure but not restrictive; the most common mistake is wearing it too loose, which lets light leak in and corrupts the ±1 bpm reading.

What part will need replacement first on the HW401?

The 90 mAh lithium-ion cell is sealed inside the ABS+PA+GF housing; after hundreds of charge cycles the 20-hour runtime shortens and the whole unit must be replaced because the battery is not user-serviceable.

What limit appears first during a long workout with the HW401?

Continuous optical sensing drains the 90 mAh battery in about 20 hours, so endurance sessions beyond that require a recharge via the magnetic cable before the next use.

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