Multiple Key Management System. Keep maximum control of keys with designated "Master" and "Duplicate" key tags. Key are loaned from the duplicate tags, while the master key stays in the cabinet. An index and cross reference manual (not pictured) is provided to track keys. Keys are cross-referenced in three ways: Lock Location, Hook Number and Key Code Number, assuring that you will always know which key is for which lock. Keys are loaned and returned in the "Key Loan Envelopes" included with the system. An account of all key loans is recorded in the provided "Key Loan Record." Yellow "Loan Tickets" are filled out when a key is loaned from the cabinet. The ticket is then placed on the hook as a visual record of the loan.