When compared to traditional mechanical lock installation requirements, the unique lock design of the Model #ML-2M mechanical lock eliminates the need to remove the back cover, no possibility of parts falling out, and no spline key is needed. Using LpLocks' proprietary Dial & Ring Assembly with a square shaft, the segments allow for ease of fitting for length, no deburring needed, and eliminates possibility of cross threading. Speedy installation reduces error possibilities. This safe lock is competitively priced and U.L. listed Group 2M (Manipulation resistant) and VdS European certification.