 Traditionally, belts have been fastened using a metal buckle; however, this type is changing for a number of reasons.Now plastic buckles are more common, and many incorporate a three-way buckle system for added security.An example of this is the 'Coplock' system, which requires the wearer to depress a third release catch before the buckles may be separated; this is to decrease the chance of the belt being released by anyone but its wearer.