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🚨 Secure smarter, not harder — your silent guardian with a loud voice!
The BlackT Electrotech BT51D is a cutting-edge 4-in-1 wireless door and window alarm sensor delivering a powerful 120dB alert. Designed for easy, wire-free installation, it combines doorbell functionality with advanced security features, making it ideal for homes, offices, and cabins. Compact yet versatile, it ensures instant notification of unauthorized entry, empowering you with peace of mind and modern protection.
| ASIN | B0DBJ2R2K4 |
| Audible Noise | 120 Decibels |
| Battery Description | Alkaline |
| Best Sellers Rank | #7,237 in Home Improvement ( See Top 100 in Home Improvement ) #5 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 | 3.9 out of 5 stars 56 Reviews |
| Importer Contact Information | Blackt Electrotech |
| Item Type Name | Door sensor |
| Item Weight | 80 Grams |
| Manufacturer | Blackt Electrotech |
| Mounting Type | Door Mount |
| Packer Contact Information | Blackt Electrotech |
| Power Source | Battery Powered |
| Sensor Technology | Contact Sensor |
P**R
Great product
Working great. And has 4 modes. 2 modes with siren type sound alerting everyone. Other 2 has single doorbell type warning sound and beep sound. So both loud and soft sounds present so can be used in day to day purpose
P**.
Good quality and VERY loud, however
The first time I ordered, Amazon sent me a different product but the next time they sent the right one. The box is small and contains the main unit, the magnet and a few double sided tapes for installation. There are 4 modes is this as indicated in the video in the product description. However, the Chime mode doesn't sound as shown in the video. It doesn't really Chime but Beeps loudly two times. I had expected that the chime mode would be like as shown in the video, like doorbell sound. The product build quality is good. Let's see how long it works.
C**A
Good product
Good product
R**A
Waste for me
Not up to the expectation
P**A
works as expected
I have kids who keep leaving the door open and we live on the ground floor, Don't want cats etc to come inside the house. This device keeps beeping till the door is closed. Very helpful
A**K
Bought two. One works fine. Another one stopping working within a month.
I bought two of them. One works fine. Another one stopped working within a month! Changing batteries or trying working batteries from the other unit didn't help. Could be a hit or miss...
A**R
Door burglar alarm
The product is very useful and price is worth
T**S
Sound Quality & Look
Sound is super loud. Installation is easy. Device looks good. Liked it at first sight. Just feeling sad that after ordering it, price got reduced by 107Rs. Now, let's see how it works in future after which will again share review here. Till then stay secure stay safe. Edit 1 - Order 2nd piece whose button is somewhat hard to slide as compared to 1st one which is smooth. Hence, instead of 5* giving 4*.
Trustpilot
2 days ago
1 month ago