The best lock cannot guard against this tecnique. To prevent this, remove two opposing screws from each leaf o Spring Latch - This latch offers little or no protection, since it can be forced open with a credit card or knife. A deadbolt in addition to the spring latch will offer more protection, however, it too can be forced open. A solid bolt, activated by a key from the outside or a knob on the inside, which slides into the door frame. The lock cannot be slipped or easily pried.
Deadbolts are only as good as the door and frame they are installed in.
Double Cylinder Deadbolt Basically the same as the single cylinder deadbolt except that it requires a key to be used from either side to function. This lock has either horizontal or vertical deadbolts. It cannot be easily slipped, pried, or forced with a wrench. This lock, like all others, requires a strong mounting surface and hardware to be effective. When buying a padlock do not economize.