Sliding Window Locks (2 Pack), Window Locks for Up and Down Windows and Horizontal Windows, Window Security Bars, Window Security Lock with Key，Adjustable Security Window Locks (Silver)

I purchased these for my single daughter, her eldest son was leaving home for the military and she wanted some added protection for her and her five year old, I bought these for her windows and she says they work great. She does use 2 on each window for that added protection and she's still able to lift her windows for air to cone in without leaving enough space for a person to come in. She just lifts the window high as she wants it and then puts a safety lock on each side. I would definitely buy this product again.

Works great and was easy to install, great value for the money, l tested them and it stops you from opening the window, great security now I can sleep with the window open a little to get some great night air

Does it's job really well!I have my AC in the one window and it always made me nervous that the window could easily be lifted and the AC pushed in or taken out either to steal it or to break into my home.These give me much more peace of mind that it would be real hard to try and do that.They are very simple to secure, once you figure out how to.Which this bring up why I knocked one star. They don't have any instructions or pictures with them to know how they attach to the window. Thank god for the product page to show how they attach because that's all you have to go by.Besides that they are great and you could put as many as you want on the windows to make it even more secure, I only did two to be safe.

These are very sturdy and well made window locks. Each lock comes with a key, which I didn't realize, but that way, you can leave the key in the lock and when you want to move it, the key is conveniently there. (There is only 1 of the keys that allows you to turn the lock in a tight space. That's the silver one.) The little plastic things are to protect your window being damaged by the screws. They are a little difficult to manage because they can fall off before you tighten the screw, but it is doable. Just takes a bit of patience and some practice.My sister commented that supposedly you can jiggle the window and get the screws lose, but that probably applies to an olden day design. I don't think these will jiggle loose, but as an added precaution, I lined up 2 in a row. (I was going to put one on each side of the window, but it only fits on 1 side.)I didn't really shop around, but at $28 for 10, you are paying $2.80 per lock set, which is probably pretty reasonable given the quality and sturdiness.

I've tried other window locks and they just didn't open wide enough for my windows. These work! They have a key for each lock so you won't have trouble finding one. I'm impressed with these windows locks.

No instructions whatsoever! I don't understand why nowadays you either get mediocre instructions or none at all. It doesn't make sense. Anyway...The window locks are useful and they work. We just installed 3 new window a/c units in our home and I was concerned about unauthorized parties entering our home through those windows. Installing these on there at least gives me some peace of mind that people can't just waltz in here through our windows.Like another reviewer, I also had to come back to the listing to see how these attach to the window. I took off 2 stars because instructions are important.

Great for not only security, but for keeping my 4yo (who is a master locksmith) from opening the windows! And very easy to install.

Little time consuming to set but at least I can keep my window open a few inches and feel a sense of security.I have some concern to marking up the frame (it’s fibrex a combo of wood fiber and some polymer). But haven’t found a solution that wouldn’t allow these to slip from initial placement.I had to set up a hook so I can keep a key close (in case of emergency).Better than not having anything….