Radar detectors are of various types. Corded radars have cords with them, and they have to be placed on the windshield. They cannot be hidden and are, therefore, useless for people who want a hidden radar detector. Cordless radar detectors are much better. They are portable and can be kept hidden anywhere in the car. Remote mounted radar detectors are permanently fixed. They only need installation once and can be hidden anywhere in the car as well. Now these radar detectors detect wavebands of various types. There is X-ray band that is used by old radars and hence, they are not useful in the modern era. There is K-band that is used by most cops around the world. These radars can camouflage their rays and therefore, are quite difficult to detect. Ka-band detectors are the best out there. They can even take a picture of the car and its license plate. It is being used by cops in some part of Europe.