2N Fortis Cylinder, Electronic knob.
The Electronic Knob enables secure, keyless access to residential apartments and is typically mounted on the entry side of the door. For added security, it can also be installed on both sides when authorised entry and exit are required. 

As the central component of the 2N Fortis Cylinder, it’s compatible with all cylinder types in the 2N Fortis range – including both Euro profile and Scandinavian oval profiles. Supplied with batteries included, it’s ready for immediate deployment.