The parameters to review for actuation include pre-travel, over and differential travel, operating force, and release force. Pretravel is the distance the actuator plunger must move from free position to operating position and overtravel is the distance it moves past the actual operating point. Differential travel is the distance from operating point to release point. Operating force is the amount of force that must be applied to the plunger to cause the switch to actuate. Release force is the level to which force on the plunger must be reduced to allow it to snap back. These are important parameters to understand when specifying what the switch must do, and therefore ultimately the type of switch to use.