Door Open Alert BITIWEND Wireless Door Sensor Chime for Office/Home/Store,Door Open Chime Window Alarm Operate Range 600ft With 58 Chimes 5 Volume Level, 3 Door Sensors+1 Plug-in Receiver, Black

Pros:Inexpensive.Very good chime module with 4 volume settings and several chime types.Small transmitter.Good adhesive.Decent range of about 50' when unobstructed.Cons:Any obstructions greatly reduced the transmission range.The chime unit is a bit heavy and can fall out of outlets due to weight over time.The transmitter burns through batteries even with light use.Have plenty of CR1632 batteries on hand as the unit fails too well once the battery falls to below 3.0 volts and each battery lasts only about 3 months.

Easy to install and loud enough while you are not in the same room.

I work in a office where the desk space is around a corner from the door. We used the sensor to alert us when someone comes in the door. So far it's been a godsend.

I will help

Great item. I use for my business and it lets us know when someone comes in. Had to replace battery already after 6 months...but still Love it.

Once i was able to figure out why it wasn't working, I just moved it lower now it's a must. I know every time someone walks through my door.

Online description did not indicate that unit won't work if more than 3 vertical feet. Totally useless in my situation where door in downstairs from where the alarm was intended to be.

It works great and is easy to ise. It is just what we needed for a great price.