Almost two years ago, I wrote a review about the Welock Touch41 Fingerprint Smart Lock. It was a solid replacement lock with very sturdy and robust build, meant for EU markets. Unfortunately, it was sub-par in terms of software features, app usage and third-party integration.

In this article, I’m reviewing the Welock SECBN51 Smart Lock by the same company. This sample, like the last one, was sent to me for the purpose of a review. Apparently, there were some changes and upgrades so I decide to see what’s improved. The fact that this company sent me a sample will in no way affect, sway or influence my opinion of the device and will just be my unbiased observations as usual.
Welock SECBN51 Technical Specification
- Model Name: Welock SECBN51 Fingerprint Smart Lock
- Type of Doors: Wooden doors, Interior Doors
- Door Thickness: 30-70mm
- Connectivity: Bluetooth
- Access: Codes, RFID Cards, Fingerprint
- Battery Type: 3xAAA
- Battery Life: 10-12 months (used 10 times a day)
- Operating Temperature: -25°C-60°C
- Material: Stainless steel with Zinc alloy, plastic.
- Price: €189,00 (use code SINDRO50)
Overview and Package Contents
The Welock SECBN51 Smart Lock ships in a hard cardboard box containing the lock, a user manual, some RFID tags and a set for installation. This set includes all the necessary bolts, pings, screwdrivers and a few extra items in case they get lost. Everything is packaged neatly and securely inside the box to prevent shipping damage.

The Welock SECBN51 looks almost exactly like the Touch41 version. It feels heavy, robust and very durable. The cylinder itself appears to be made in Germany, which is a subtle promise for quality, if that can count for something these days.
On the face of the handle, lies a pairing button next to the fingerprint reader. This button also needs to be pressed to wake up the lock before the reader can be used, as it’s sleeping when it’s not operated. Since they are meant for different door sizes, the indoor knob is smaller than the one on the Touch41 variant.

The SECBN51 model is adjustable and can fit on doors with thickness from 30-70mm. The knob can be moved easily by releasing the small hex screw that’s holding it in place. It’s machined really smooth and feels nice when handled.

The Welock SECBN51 is powered by 3xAAA batteries, found under the main rubber lid. When the batteries die, you can attach a 5V power source (Micro-USB) to temporarily power the lock and open it like you normally would. It’s worth noting that Welock claims a 10-12 month battery life on a good set of AAAs, opening the lock 10 times a day.

To utilize each and every feature the WeLock SECBN51 offers, you would need their Bluetooth gateway hub. It’s a new version labelled as WIFIBOX 3. It can capture BLE and 433 MHz signals and relay them to your controller. I received one with the lock package.


Installation
Installing the WeLock SECBN51 Smart Lock was very easy. I had a similar experience with the Touch41 model, which I mounted only the included tools. As it’s a replacement lock, it does require removing your existing cylinder, so some skill is definitely needed. They did a great job of detailing the process in the manual.
I decided to install and test out the WeLock SECBN51 lock on a back terrace door of my home. This is a generic PVC door, suited in thickness and cylinder distance for the SECBN51. I did cheat a little on this one by using my own screwdriver, which was easier to handle. Here’s how it looked like after I was done:


The small display on the WeLock SECBN51 model is quite useful. It displays the date and time, which changes to the current status or operation being conducted, like reading fingerprint. The reader itself is very fast and accurate, after being properly set in the app.


For comparison, check out how the Touch41 model looked like once installed on one of my interior doors.
App Setup and Usage
The biggest grudge I had when I tested the Touch41 model was the app. It was an outdated, bad looking piece of software with sub-par user experience. Analyzing it a bit, I get where they come from. They wanted to make it usable, without minding too much on how it actually looks like. They failed.
Sadly, the app is still very bad.
I was hoping the would have fixed it by now, but the app still looks like it was made in 2006. Yes, it has a bunch of menus and features and everything required to make the lock operational and functional, but the UI is abysmal.
And requiring a phone number to create an account? That’s a hard NO.
Final Thoughts
The WeLock smart locks are some of the best locks in terms of hardware I’ve ever seen, but they are severely lacking in software. The difference is so paradoxical that it makes me question the entire thing. What’s the purpose of a smart lock with a bad app?
In all honesty, the smart lock itself operates nicely. The fingerprint works great, the tags work great, and the principle of operation is very reliable. Unlock to latch the cylinder and turn the lock—a simple yet efficient mechanism. Even the app works better than the previous version I tested with the Touch41 model.
I guess you could setup the lock in the app and integrate it with third-party controllers like Alexa or Google Home. However, I feel like I’m giving too much data to make this happen. There are better alternatives out there that have great apps, Home Assistant integrations and don’t require a bunch of weird permissions on your phone to use them.
The WeLock SECBN51 Model costs €189,00, but you can use code SINDRO50 to get a €50 discount.
Assuming this lock uses BLE and that there’s some sort of additional security on top of IRKs, I wonder if one could dump encryption keys from the gateway firmware and write an open source Home Assistant integration using Bluetooth proxies. I kinda hope the lock isn’t using 433 Mhz for communication, because that’d probably mean it’s clear text or using bespoke encryption.
Yes, it might be possible. The lock uses Bluetooth indeed, but I haven’t got the time to go after something like this.
Especially since you won’t be able to utilize all features anyway and would still need to use the app.