I would have liked it to have a volume adjustment. I had to stick something in front of the speaker. But overall, it's very convenient

I installed it yesterday on my balcony as an auxiliary motion detection alarm system. The distance it detects motion is only two to three meters, so it barely works for what I bought it for. It might be perfect for motion detection only at a door. I should note that a similar Chinese one I had for five euros for the same job worked for several years outdoors, of course without getting wet, and with sensitivity for many meters. But I liked the idea of having the sound notification inside my space, so that's why I got this one, but I'm not sure I will keep it, at least not for this use.

I do not recommend it as it does not work properly. It needs to be passed at a distance of 1 to 2 meters from the front and still sometimes does not hit. The maximum distance without obstacles is only 20 meters, I returned it. Get the SF20R/VSC-20 instead, it is much better

Very disappointed with the purchase, I bought it because of the many positive reviews. The sound notification button doesn't work well and the LED lights stay on permanently, resulting in the batteries needing to be changed frequently (requires a total of 6).

It is a good case for its price, it has a 1-second delay but it doesn't affect much. It has a light to inform you without sound, otherwise it is worth its money

I ordered 2, one of them didn't work. As soon as I requested a return, they accepted it without me having to send anything back. I suppose they often have this problem. It's good for the money. Ideally, I would like it to have adjustable intensity and if it hits once, it hits again after 4-5 minutes instead of continuously hitting whenever it detects movement.

I just put it today and the first experience is very good. It reaches a distance of 10 meters that I have it, but there is also an obstacle of three walls, while I have it closed in a plastic cabinet. Even the cricket was satisfied :p

In 20 days, the button that opens and closes broke, so you have to remove the battery to make it stop.

It's great. I bought it for my mom so she can hear when she gets up, as she is elderly and has low vision, and it works perfectly

The machine is very good.
If you tune it once as instructed and remove the batteries, it does not lose frequency. It has very good and powerful sound (It has many options for sounds, but not for volume). It has good range even with walls interfering

It works great, exactly what I needed. Convenient that it has the on/off button on the receiver and you can easily turn it off when you don't want it to go off.
The sensor's "eye" has a wide detection range and perimeter, so in order to prevent it from going off randomly or multiple times when someone passes by, I have placed it in an open box only from one side to limit its field of vision and only see straight ahead. Now it only goes off once when someone passes in front of it (I have it on the staircase entrance of the building on one of the steps).
I still have to see how often the batteries will need to be changed, I hope they last a long time because it requires a total of 6 AA batteries

We have been using this device for over three months without needing to change the batteries, so it does not have a significant battery consumption. The range at which it emits the signal is quite large, meaning that within the 10 meters it comfortably covers, you can easily carry the receiver with you when you are in the warehouse and be notified. It is not very, very fast, meaning it has a delay of almost one second from the moment it reads the input until the moment it rings the bell. You just need to take that into consideration

It works flawlessly, with great range. Daily use, the receiver needs batteries about every 3 months. The transmitter does not.