The ATRIUM A22K controller is a hybrid controller that works perfectly with the most popular Wiegand card readers or with the KRYPTO high security solution. The A22K controller has the best of both worlds. The KRYPTO high security solution is the easiest solution to use and manage DESFire EV2/EV3 smart card credentials on the market. In the event of a complete power failure, the unique encryption keys will be automatically downloaded securely into the KRYPTO readers upon power restoration for an effortless system start up and management. ATRIUM’s efficiency will simplify your life.