a lock affixed to conventional hand brake structure , and by which , when the lock is unlocked , the hand brake can keep retain its normal functions . when the lock is locked , the hand brake can only be pulled up and cannot be released by pressing down a push button , thus locking is assured . such structure is has the function of theft - proofing with convenience of use , also has the practicality and improveness in preventing from towing a vehicle away by thieves .