The 30 mm metal safety limit switches conform to EN 50041 and have been developed to provide a range of options including a choice of snap-acting, slow-acting and break before make (BBM) with 2-, 3- and 4-circuit configurations and a choice of actuator heads. The distance between the horizontal mounting holes is 30 mm. The operator heads can be rotated in 90 deg increments for easy mounting. Allen-Bradley/Guardmaster limit switches can be used in other applications other than guard doors, for example on moving machine beds, crane arms, lifts, elevators, etc. Operation of these limit switches is achieved by the sliding action of the guard or other moving object deflecting the plunger or lever.