SECRUIDoor Chime with 2 Sensors, 500ft Operating Range 52 Chime Adjustable Volume with Mute Mode LED Indicators 1 Plug-in Receiver 2 Magnetic Door Alarm Sensor for Home Security & Office

I do recommend this system, easy to set up. Only wish the volume had another lower volume to it. At the low volume, still kinda loud overall I like it

So batteries for these run anywhere between 4 and $10 depending on where you can get them from and I have only seen them be sold individually and not in packs like double A's, on the bright side I just had to replace the batteries so they do last a while. Easy installation, you can choose to use the peel and sticks which have amazing hold, or you can choose to enter them with screws that are provided. The binger is pretty loud, it has multiple sound settings as well as tones to choose from. They do work really well, they will go off anytime you open the door window or whatever you have them attached to. As far as range I have them attached to my front and back door, but I have the actual plug-in that the sound comes from in the master bedroom so it's got some pretty good range.

Exactly what I was looking for and it was super easy to install...and so many sounds to choose from as well.

It worked great for a while. Easy to set up( at least I thought so) it stopped working after about two hours. So I redid everything. The front door started working but I could not get the back to work . I gave up. Before I closed my shop for the day the front door just started ringing ! Off and on off and on. Door never opened! Hope it starts working right tomorrow Update: I played and played with it again. Can only get one to work, and it still goes off once in a while even if the door does not open! Not helpful

My mother in law has alzheimers and tends to wander around at night while we're sleeping during her visits. I used to keep a bell on the door but we sometimes slept through it. On her latest visit, she had went down the stairs by herself, tried to make an empty pot of coffee, and left the water running. I was so worried I couldn't sleep. I was able to order this door alarm and have it delivered same day. This device is now set up so that anytime she opens the bedroom door, an alert goes to my bedroom so we can reroute her back to bed. It came as a pack of two sensors so I put the other at the front door as well. Volume and sounds are adjustable, and we felt so much better at night knowing where she was.