A bolt engaged by turning a knob or key, rather than by spring action.
Deadbolts come in three primary varieties: single, double, and lockable thumbturn.
- Single Cylinder Deadbolt: This is a simple deadbolt lock which is activated or opened from one side through a key while there is a thumb piece in the interior side. These types of locks are used in the doors which do not have any breakable glass near the thumb piece turn. As the intruder might break the glass, turn the knob and enter in.
- Double Cylinder Deadbolt: This is a deadbolt lock that is activated through key from both the sides. These can be used in the situation where there is a breakable glass near the knob. But these also hinder escape in situation of fire etc.
- Keyless Cylinder Deadbolt: These are the most easily operated deadbolt locks that can simply be opened by a fingerprint scan or password and can be closed with a button or knob.
- Classroom-function (thumb-turn only unlocks door)
- Exit-only function (no external cylinder)
- Push-button deadbolt (mechanical or electrical)
- Single cylinder with removable thumb-turn
Brands of Deadbolt Lock: Schlage, Kwikset, Yale Security, Code-a-key, LockState, Master Lock