DoorKing Proximity Card Readers A unique feature of the DKS proximity card reader product line is that the card readers are compatible with both passive and active tags. This allows a mixing of different cards and tags to achieve desired read ranges in different locations without having to install a second card reader or carry two tags. These readers feature a cosmetically appealing design that will blend with any architectural design and offer high durability and reliability. AVI (or Automated Vehicle ID) systems operate in the same manner as proximity card systems, but with longer ranges. A typical AVI-system places a tag on the vehicle, rather than having the user carry it. In this manner, a gate system will open automatically as the vehicle approaches with a properly credentialed tag. This provides convenience and is ideal in applications where only authorized vehicles are allowed entry.