1. How does the alarm detect door or window opening?

The sensor and magnetic strip work together. When the door or window opens and the magnetic connection breaks, the alarm activates instantly.

2. How loud is the alarm sound?

The alarm produces up to 120–125dB sound, helping alert occupants and deter unauthorized entry effectively.

3. Is wiring required for installation?

No, it is completely wireless. Simply attach the sensor and magnet using the included adhesive for quick installation.

4. Where can this alarm be used?

It is ideal for homes, apartments, offices, cabins, shops, warehouses, windows, doors, and other entry points.

5. Can it be used as a calling bell?

Yes, its 4-in-1 design allows it to function as a wireless calling bell as well as a door and window security alarm.

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Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

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BlackT Electrotech (BT51D) 120dB Wireless Door Bell & Window Alarm Sensor – 4in1 Smart Calling Bell for Home, Office Cabin & Property Security – No Wire, Easy Installation

Product ID: 650964047

Details

Battery Description
Alkaline
Brand
Blackt
Colour
white
Compatible Devices
Home Security
Power Source
Battery

🏠4-in-1 multi-use security

🔊120dB piercing alert

🛠️wireless, no-fuss install

59.32 DT

Duties & taxes included

In stock

Sold byAmazon TunisiaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Description

🚨 Stay ahead of intruders with the BT51D’s smart, loud, and wire-free security!

INSTANT 120 D B ALERT - Cut through the noise with a powerful alarm that demands attention—perfect for any entry point.
4 IN 1 SMART SECURITY - Combines doorbell, alarm sensor, emergency alert, and calling bell in one sleek device.
COMPACT MODERN DESIGN - Seamlessly blends into your space while delivering maximum security with minimal effort.
VERSATILE FOR ANY SPACE - Ideal for homes, offices, cabins, and shops—protect what matters wherever you are.
EFFORTLESS WIRELESS SETUP - Peel, stick, and secure in seconds—ditch the wires and complicated installs for good.

The BlackT Electrotech BT51D is a compact, battery-powered wireless doorbell and window alarm sensor delivering a piercing 120dB alert. Designed for easy peel-and-stick installation, it functions as a 4-in-1 security device—doorbell, alarm sensor, emergency alert, and calling bell—perfect for homes, offices, and cabins seeking hassle-free, effective protection.

Specifications

ASIN	B0DBJ2R2K4
Audible Noise	120 Decibels
Battery Description	Alkaline
Best Sellers Rank	#8,545 in Home Improvement ( See Top 100 in Home Improvement ) #8 in Home Security Alarms
Brand	Blackt Electrotech
Built-In Media	magnet
Colour	white
Compatible Devices	Home Security System
Control Method	Touch
Country of Origin	China
Customer Reviews	4.1 4.1 out of 5 stars (98)
Importer Contact Information	Blackt Electrotech
Item Type Name	Door sensor
Item Weight	80 Grams
Manufacturer	Blackt Electrotech
Model Number	BT51D
Mounting Type	Door Mount
Number of Items	1
Packer Contact Information	Blackt Electrotech
Power Source	Battery Powered
Sensor Technology	Contact Sensor
Size	Small

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59.32 DT

Duties & taxes included

In stock

Sold byAmazon TunisiaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Tunisia.

Secure transaction

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Ravi S.

I loved the variety of products available. Will definitely shop again.

2 months ago

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1 week ago

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