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Round aluminium-alloy case, black silicone strap, touch-and-button control

allentian

allentian E400 Smart Watch 29-35mm 15-21 Day Battery

SKU CH-A456-4TEH8

Tracks heart rate, blood pressure, glucose, temperature and sleep with 15-21 day battery life

  • ColorBlackLeather
  • SizeMedium
  • CompatibilityAndroid / IOS
  • Sports TeamNO
  • Tracks heart rate, blood pressure, oxygen and temperature for full health picture
  • 15 to 21 day battery life means less frequent charging
  • 29 to 35 mm aluminum case with IP touch and button control fits most wrists
  • Bluetooth calls, alerts and remote selfie keep phone in pocket
  • Silicone sport strap and 105 g weight stay comfortable all day

Who this watch is for

The allentian E400 is a new smartwatch built for men who want daily health metrics and phone alerts on a compact 29-35 mm round dial. It tracks steps, heart rate, blood pressure, blood oxygen, body temperature and sleep patterns while also handling Bluetooth calls, message reminders and remote camera control. The aluminium-alloy case weighs 105 g and comes with a sporty silicone strap in black, red, blue or dark-skin finishes.

What it replaces and when to upgrade

It replaces a basic step counter or a phone-only notification setup by adding continuous heart-rate, blood-pressure and SpO2 readings plus on-wrist calling. The jump is worth it if you need multi-parameter health logging without carrying a bulky device and can accept 15-21 day battery life between magnetic charges. Buyers who require certified medical-grade accuracy or swim-proof water resistance should look elsewhere.

Installation and common issues

Pairing is done by downloading the companion app on Android or iOS, enabling Bluetooth and following the on-screen bind process; the watch uses touch and button controls for navigation. The magnetic charging cable snaps to the back for power. Common issues include occasional sync delays after firmware updates, inaccurate blood-pressure readings if the wrist position shifts, and the IP-rated waterproofing not being suitable for swimming or high-pressure water.

Highlights

  • Tracks heart rate, blood pressure, oxygen and temperature for full health picture
  • 15 to 21 day battery life means less frequent charging
  • 29 to 35 mm aluminum case with IP touch and button control fits most wrists
  • Bluetooth calls, alerts and remote selfie keep phone in pocket
  • Silicone sport strap and 105 g weight stay comfortable all day

Specifications

ColorBlackLeather
SizeMedium
CompatibilityAndroid / IOS
Sports TeamNO

Questions about this item

What wrist size does the 29-35 mm aluminum-alloy case with 105 g weight fit?

The case diameter spans 29-35 mm and weighs 105 g; the sporty silicone strap adjusts to most average adult wrists.

How do I charge the E400 using its magnetic cable, and what step do users often miss?

Snap the magnetic data cable onto the back contacts; the step many miss is aligning the pins until the watch vibrates or shows the charging icon.

Which user-replaceable part will need attention first on the E400?

The magnetic charging cable is the only accessory designed to be swapped; the silicone band is fixed to the case and not intended for user replacement.

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