Bump Proof Keypad Deadbolt
This image is originally part of the article Reasons Why A Keyless Entry Keypad Deadbolt System Is Worth Buying
Mechanical push button deadbolt systems are very convienient in that they don't require elctricity to work. The problem however is that many can be "bumped" and opened. This deadbolt is one of a number of mechanical deadbolts that is bump-proof.