Toddlers are curious, and sometimes you need to keep them out of certain rooms (like the pantry, office, or basement). The GlideLok is a clever solution because it mounts on the TOP of the door, completely out of their reach. It's made of durable painted metal (not cheap plastic), so it won't break easily. Installation requires drilling one small screw (included) into the top of your door frame. Then, the lock slides over a peg to secure the door. Adults can easily lock and unlock it from either side of the door, which is handy. It fits most standard hinged doors up to 1-3/8 inches thick (or thicker if you remove a spacer). Important: It works on hinged doors with knobs or levers, but NOT on sliding doors (like bifold, pocket, or patio doors). This 3-pack lets you secure multiple doors around the house. It's a more discreet and reliable option than doorknob covers that kids can sometimes figure out. Just make sure you can reach the top of your door to operate it! A popular choice for babyproofing that actually works well.