Addalock - (1 Piece) The Original Portable Door Lock, Travel Lock, AirBNB Lock, School Lockdown Lock

I live in an apartment and work from home some days. One day I was on a conference call when I heard a knock at the door. The man behind the door shouted "maintenance," but he literally gave me 10 seconds to get to the door before he just started unlocking it. The landlord didn't provide me any warning that maintenance would be installing new air filters that day. After that incident, I knew I needed some sort of lock.I narrowed down my options between the Addalock and a security bar. The reviews for security bars are mixed: the success or failure highly depends on finding the right angle and using the bar on the correct flooring. Also, while one of the more inexpensive security bars on Amazon is cheaper than Addalock, the better-reviewed ones are more expensive.I could not figure out how Addalock worked from the pictures. My brain just wasn't putting it together. So I searched "Addalock" on YouTube and there were several videos, including one from a home shopping network, that demonstrated it. If you are like me and the pictures aren't doing it for you, I highly suggest you watch one of the Addalock videos.As others have said here, this works best if you have a quarter's width between the door and the jam. I didn't have a quarter, so I used 2 and then 3 credit cards. I had ample space, so I ordered it.My front door has a dead bolt and a doorknob lock, but my doorknob lock hasn't worked since I moved in. The doorknob locks, as in the knob won't turn when the lock is engaged, but the latch doesn't catch in the strike for some reason. Maybe it's not long enough to extend into the strike. So right now I am using my regular dead bolt and the Addalock on the broken doorknob lock. I also tried installing it on the dead bolt, but my dead bolt could not push all the way through the Addalock plate into the strike. The Addalock still WORKED, of course, and no one would be able to get in, key or not, but it just seemed like more security against intruders to use the dead bolt and the Addalock on the lock that's broken. If I am trying to keep out unexpected landlord visits, though, then it wouldn't matter where I installed it because no one with a key could get into the apartment.When I first used Addalock, the door didn't open fully, but I could get it open a tiny crack. I realized that I wasn't properly lining up the stainless steel part that inserts into the strike. Take the time to push that plate into the strike of your door jam and then slowly close your door. After that, I couldn't move the door *at all*.I am so thrilled to have this portable lock that I can attach and remove whenever I please and one that won't violate the terms of my lease agreement. It's VERY easy to use, but it's just not intuitive from the instructions for some reason, at least for me. I am a spatial learner, so the videos and getting my hands on the Addalock helped. I was able to install it in under 10 seconds and remove it in under 10 seconds the first time I tried it.*EDIT: (10/15/2015)Maintenance decided to make yet another surprise visit without warning. As it turns out, he read the apartment number incorrectly.This time, unlike last time, I had the Addalock engaged. He could not open the door. He tried multiple times. I even heard him banging his shoulder into it. This lock really does work. I was able to answer the door on my own time rather than just have a maintenance man barge in on me in the middle of the day. If you're a renter with an inconsiderate or incompetent landlord, I highly recommend you purchase one of these for all your doors.

I tried it immediately on my door, it was very easy to setup.

La cerradura portatil viene con un estuche practico para llevar cuando viajas, como ventaja principal es la seguridad en la puerta, Lo recomiendo por su practicidad y calidad

Addalock was recommended by a family member. I am very pleased with the ease of installation and the sturdiness it offers. Even if you forgot to lock the dead bolt with the Addalock in place no one could gain entry to your home, apartment, hotel room, etc.I highly recommend this to anyone as it provides a little extra peace of mind, safety & security.

This is supposedly the original Original portable door lock, not an imitation.It is a nice touch it comes with an Addalock nice pouch too.I am glad I bought two.