INSTALLATION REQUIREMENTS: The Door Monkey works with standard 1-⅜" thick interior doors and standard rectangular door stop moulding. It does not fit some non standard doors and & door frames. Please review the image of the installation requirements before ordering. NO TOOLS OR TAPE REQUIRED: Our unique design allows the Door Monkey to be installed in seconds without the need for tools, tape or hardware. NO ACCIDENTAL LOCK-INS: The Door Monkey is operable from both sides of the door so there is no chance of your child locking you in a room. VERSATILE DESIGN: The Door Monkey is not only an incredibly effective door lock, it also doubles as a pinch guard. The door is always secured in a partially cracked position, helping to prevent painful pinch injuries. WORKS W/ DOOR KNOBS & LEVER HANDLES: The Door Monkey simply clamps to the edge of your door in seconds and works with any style of door knob or lever handle. (It does not fit some nonstandard doors and & door frames.)