MUL-T-LOCK CLIQ MT5+ KeysMT5®+ CLIQ® integrates the innovative and proprietary CLIQ technology developed by ASSA ABLOY with the patented MT5+ mechanical locking systems developed by Mul-T-Lock. CLIQ technology is based on miniature microprocessors embedded directly inside the key and cylinder cores, creating an intelligent electromechanical system that is flexible and secure.


  • Data tracking
  • Time based permission
  • Add or eliminate keys on your own using a control key
  • Software, programming device and control key to manage the system


1  The key is inserted into the cylinder; when the cylinder’s pin meets the key’s contact strip, an electronic wakeup signal is sent.
2  The cylinder wakes up and sends a random 64-bit number to the key.
3  By using the 3DES encryption algorithm, the key encrypts the number and sends the encrypted response back to the cylinder.
4  The key’s response is compared to the cylinder’s encrypted number.
5  If there is a data match and the key is authorized within the current time window, the blocking mechanism is released and the key can turn the cylinder; if not, the cylinder will remain locked.
6  A log of the activity - including user, data and time - is automatically stored in the memories of both the cylinder and the key for later retrieval.