This kit comes with a lot of tiny parts to assemble and match your existing key lock for use of your original key. (lock keys/springs/detent pins) I disassembled my original (damaged) lock for comparison locations of the lock key detents to assemble the new lock. Make sure you track everything during disassembly of your old lock to properly assemble the new lock. Assembly is not an easy process, but if done correctly, the new lock works perfectly with your existing key. This process takes patience. Tracking of individual parts (locations) is critical to success.