The square that sticks to the surface measures 1.4"x1.4". Additionally, to ensure a complete proofing experience, every lock features a pre-applied 3M adhesive that works on all surfaces including wood, glass, marble, and metal. With pre-applied 3M adhesive, the cupboard door lock can be easily installed without drilling. Clean the area that you’re sticking it to with alcohol Peel off the adhesive cover on the lock Stick the lock to the surface of your cabinet, drawer Use the catch bars included with this pack if the hook does not get locked on the other side Leave the locks to set for at least 24 hours How to remove? The baby locks can be easily removed without damaging your furniture by following these steps: Heat the installation surface using a hairdryer for about 15 seconds Pull the lock gently Re-apply heat if necessary Use alcohol/detergent to remove any adhesive residue