No way anyone can pick your lock with this on it. I bought them for all our doors and sent them to my parents as well. These are extremely easy to install yet impossible to unlock from the outside. It is a relief knowing no one is going to quietly pick the lock on my parents' house (or my house) and break in as we sleep. With this attached, that dead bolt is absolutely secure and impenetrable from the outside, yet easy to open from the inside with just a flip of the finger -- it will take more time and effort for you to unlock the dead bolt than to disengage this. I would never own a door without a dead bolt and I will never have a dead bolt without one of these on it. If you rent or go to college, you can easily uninstall it and take it with you when you leave.

There is a recent and alarming rate of key bumping across the country. Don't make it easy for criminals by not securing your dead bolts. Just use this easy to install and theft-proof device. I have purchased two of these and it only takes less than 5 minutes to install.

You do not need to completely remove the deadbolt to install. From the inside of the door, just loosen the two deadbolt screws, slip the two rings behind the dead bolt and re-tighten the two screws..That's it: After you're finished, when you want to secure, just flip down the latch over the dead bolt. There's no way for someone to turn a key and open the deadbolt, or a key bumper to open the deadbolt once the latch is down. Note: This security device can only be used from the inside. There is no way to use it from the outside of the door to secure the deadbolt once you leave your home.

IMPORTANT: If you're worried about locking yourself out, don't worry. The latch flips up firmly.and stays in place.

You can visit YouTube and see how key bumping works. By installing this simple device, you can feel secure while you're in your home.

I highly recommend.

My apartment door only has one deadbolt that unlocks with a key from the outside. My previous apartments have had an additional interior deadbolt or security latch. I wanted to add a deterrent and extra level of security for when I am inside. This latch is very easy to install and makes me feel very safe.

Easy to install and felt very safe. Only thing I worry about is if someone uses the dead bolt lock while you are out. You are locked out and hope you can call someone inside.

Okay, this sucker was awful to install. Not all door bolts are created equal. It ended up being too thick and the bolt screws didn't then meet with the bolt plate. I had to jerry-rig it and it did work in the end, but only because I'm crazy persistent. In the end, it works perfectly fine and does the job. Just be aware that it might not work for your particular bolt.