Intermatic SP440B Wireless Window Alarm Sensor - White | Home Security System for Doors & Windows | Easy DIY Installation for Apartments & Houses

I ordered four Intermatic Wireless Window Alarms and had no problems installing them on various windows. All four alarms were loud enough for my purpose and that is to maybe scare off the intruder or alert me that something is wrong.I only turn our alarms on when we are leaving the premises, so my battery replacement won't be as often as others who leave theirs set to on much or all of the time.I did use the transparent double-sided tape (it is lined with red adhesive that is to be pulled off before applying tape) which I bought in the paint/hardware department. I don't think the alarms will be falling off even in our desert heat. Make sure you clean the surface well before applying the alarms.Great little alarms for that added protection without spending a lot.These alarms work well for me. I have a 2 bedroom apartment, and if one of these alarms goes off I will definitely hear it. It might not be loud enough to protect a bottom floor if your in a 2 story home however. I put them on my windows and doors, and i can rest a bit easier at night knowing that i will at least hear them coming if their is a break in. The only real compliant would be the batteries. These small g13 batteries don't last a huge amount of time. I save them by turning them off when im home. I bought a 100 pack on amazon cheap so i guess i cant complain much. Anyways I would recommend.These things are ok. If you live in a small apartment/house, and are sleeping (no background noise), you may hear the alarm? But, there is NO way in HEEL that it's 90 db! Another problem is: if the two pieces are not lined up "precisely" The alarm goes of!I ordered this product in hopes it would be superior (louder) to GE similar product (which I purchased earlier). It is NOT! The GE product is clearly superior!I promptly returned these because I thought they would be louder. I want it to be twice as loud!!! If a thief wants to break in - as one already did into my apartment and also did into another person's in my ground floor complex- this is what they did at his apartment- He had some kind of alarm like this on the window and they quickly just turned it off - so if nobody's home it won't matter one bit. If you are home, then it could help warn you. It probably would be loud enough to do that.It is so cheap it might as well be free :) It is not THAT LOUD, it is as loud as someone talking, not ear piercing. However it is loud enough to be heard from my master bedroom, so that is good enough for me. I initially ordered two of these, they popped right on the window in seconds. I already ordered three more along with a 20 pack of AG13 batteries to cover my front windows. They are very small, cheap, and work.I was disappointed in the battery situation. The instructions say to remove a tab attached to the batteries, but there is no tab. I measured the battery voltage on the bad ones. It was very low. Amazon's return was easy, print a label, use the same box and drop it in the mailbox. If your unit isn't very loud, ship it back to Amazon.We used these years ago back at our apartment. One night our window sensor began alarming. I sent my wife to hide and call 911 while I grabbed my hunting knife. Turned out, the adhesive just wasn't strong enough to securely hold onto our wall due to the wall texture. But if you can't go with an actual security system, this is surely better than nothing!I purchased this based on the great recommendations and i am dispointed. after just a couple days it has already fallen. So if you et it you will need double sided tape. very irritating. otherwise noise level is good...you would definitely hear it if someone tried to break in.