Double Cylinder Lock Vs Single. A single cylinder deadbolt has a slot for a key on one side while the other side features a knob or turning mechanism of some sort usually a thumb turn that looks like a simple lever that turns much like a key would. Double cylinder deadbolts are locks that require a key to open from both the inside and outside. Single and double cylinder deadbolts and door locks single cylinder deadbolts and handlesets are operated with a key from the outside but do not require a key for locking or unlocking from the interior of the property.
Single and double cylinder deadbolts and door locks single cylinder deadbolts and handlesets are operated with a key from the outside but do not require a key for locking or unlocking from the interior of the property. Single cylinder locks are more common than double though that trend is starting to change.
Deadbolts with a captured key feature operate like a single and double cylinder lock.
Double cylinder locks is the number of cylinders. Double cylinder deadbolts are locks that require a key to open from both the inside and outside. Double cylinder deadbolts or handlesets require a key. Double cylinder locks is the number of cylinders.
