These have literally been a life saver for us and our 2yr. She learned how to open doors. So I put it on the front door, so she couldn't get out is we walked out of the room. Now I have them on all the doors. So that she can't get into the older kids rooms an possible get something that could hurt her & the bathroom door. She was walking in on everyone lol. Also on the inside of our bedroom. Bc she's SNEAKY an quietly (ONLY time she's EVER quiet) gets out of bed an wonders around the house. PLUS works GREAT on older kids too! My 13yr 90% time can't get the front door open. Lmao!! They are kinda noisy too. So it very hard for anyone to open a door without being heard. SO if u have teenagers they are great at helping you hear if they try to sneak out or in. Bc even if a door is opened from the outside. They still make a noise from the doorknob turning. Just a little FYI for parents with SNEAKY older kids too.