LEHOUR sliding door locks are perfect for our windows and sliding doors~ They are super easy to install and relieves our headaches on securing the windows and sliding doors. We are amzed by it's functionality ~ Just peel off the tape on the back of the door/window lock and place the door/window lock gently on the surface and hold it for about a minute to make sure it's sticking to the clean surface. No tools needed whatsoever~ It's suitable to be used on all smooth surfaced. Very functional~