We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Square smartwatch with black leather strap, 28mm case, 180g weight

allentian

allentian Et540 Smart Watch BlackLeather 28mm 180g

SKU CH-W828-8EKDN

A smartwatch with Bluetooth calling, ECG, blood-pressure and blood-oxygen monitoring, sleep tracking and multi-sport modes in a 28 mm case weighing 180 g

  • ColorBlackLeather
  • SizeMedium
  • CompatibilityAndroid / IOS
  • Sports TeamNO
  • ECG heart-rate monitoring for health insights
  • Bluetooth calling keeps you connected hands-free
  • Blood-pressure and SpO₂ tracking for daily wellness
  • Multi-sport modes with sleep analysis support fitness goals
  • 28 mm square dial and magnetic charging suit everyday wear

Compact smartwatch for everyday health monitoring

The allentian Et540 is a lightweight wearable designed for users who want continuous wellness data on a small wrist. Its 28 mm square case and 180 g weight suit a range of wearers from teenagers to adults. Touch and button controls provide quick access to core functions without a steep learning curve.

Bluetooth calling and notifications rely

The watch handles calls, reminders and remote camera triggers only while connected to an Android or iOS handset. Battery life stays under seven days, so weekly charging via the magnetic cable becomes routine. Life waterproof rating protects against splashes and sweat but not swimming or high-pressure water.

Health sensors cover the essentials for daily

Built-in modules measure heart rate, blood pressure, blood oxygen and sleep patterns to give a broad picture of wellbeing. Multi-sport modes add activity context, while the TPU strap and classic buckle keep the device secure during exercise. No onboard GPS or cellular radio means the phone must remain nearby for location tracking.

Highlights

  • ECG heart-rate monitoring for health insights
  • Bluetooth calling keeps you connected hands-free
  • Blood-pressure and SpO₂ tracking for daily wellness
  • Multi-sport modes with sleep analysis support fitness goals
  • 28 mm square dial and magnetic charging suit everyday wear

Specifications

ColorBlackLeather
SizeMedium
CompatibilityAndroid / IOS
Sports TeamNO

Questions about this item

Which colour and strap option should I choose for the Et540?

The Et540 comes in black leather, TPU black, red, blue and brown with a classic buckle strap; pick the colour that matches your daily wardrobe and the TPU material for lighter workouts.

What does the 28 mm case diameter mean on my wrist?

A 28 mm square case sits compactly on smaller wrists, keeping the 180 g weight balanced while still showing call alerts, health metrics and notifications clearly.

How does the Bluetooth calling work with Android and iOS phones?

Pair the Et540 via Bluetooth to Android or iOS, then make and receive calls directly from the watch using the built‑in speaker and microphone.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.