The care and maintenance of a barrel lock and meter key set is important. These high-tech lock and key sets can deliver years of service if they are maintanted in the right way. Most of these lock and key assemblies require that they are kept clean and free of dirt, mud and debris. In fact, the plastic cap that comes with the meter key should always be used and never discarded. This simple cap can protect the plunger assembly and prevernt dirt from collecting on the various metal components. Immediately after use, the meter key or plunger should be wiped dry if in a wet environment and re-covered with the plastic cap. Taking these simple steps serve to keep the lock and plunger key in good working order. Work with an expereinced meter key professional to ensure that you are using the right key for the job at hand.