Blanksystems also specialize in custom designed covert Surveillance systems for commercial and domestic clients’. Covert security cameras can be stand alone, completely discrete systems where occupants are unaware of a video surveillance presence or be part of a larger traditional system.
Traditionally the visual "in your face" approach to placement of security cameras serves a dual purpose. Not only are they recording the events for future reference, but their presence has a certain  deterrent value associated with it
However, not everyone is deterred and others will look to conceal their crime out of the view of the surveillance system.
It could be housebreaker. Or a clerk skimming sales at the register, or a shoplifter stealing your merchandise.  
Covert cameras add an additional layer of defence by covering potential blind spots or frequent areas of crime in your business. This is why complementing traditional security cameras with covert or hidden cameras can lead to getting the whole story.