This term refers to a metal plate, either curved or flat, that is installed on the door frame opposite a door lock. The latch or bolt of the lockset actually protrudes into the strike when the door is closed and/or locked. The proper installation and adjustment of the strike is critical for the secure and reliable operation of the lock. In short, the strike is the other half of the lock! Strike adjustment is one of the most common repairs that locksmiths make.