thus a first air gap 47 see fig1 and 11 is created between the outer surface of plunger 44 and the inner surface of spool 36 first air gap 47 helps to avoid the build up of residual magnetism along plunger 44 and further aids in dissipating the build up of heat in solenoid 35 when the solenoid is energized this has several advantages first air gap 47 helps to avoid expansion of spool 36 and a resulting shrinkage of the inside diameter of spool 36 which otherwise would cause friction or binding between plunger 44 and spool 36 during travel of the plunger towards front cap 38 when solenoid 35 is energized second solenoid 35 is able to be operated at a lower voltage than if no air gap were present because heat does not build up inside of solenoid 35 heat build up would otherwise increase the resistance of wire coil 37 thus requiring more voltage to operate solenoid 35 when solenoid 35 is energized plunger body 46 is by the resulting magnetic attracting forces moved toward front cap 38 see fig1 during its motion caused by magnetic attraction the plunger tip 48 exits the front cap 38 through hole 39 and strikes an aluminum or other non ferrous metal actuator pin 50.