fig2 as emanating from the light outlet aperture 64 and shining on a lateral work area adjacent and in axial alignment with the drive stem 26 the lateral work area being occupied in part by the socket 28 however as will be explained hereinafter the switch 20 as shown in fig2 is in its 34 off 34 position so that the light beam 68 as shown in fig2 will not exist until the switch 20 is moved to its 34 on 34 position which is shown in fig5 referring now to fig3 the fiber optic element holder 60 is shown in perspective the holder 60 is polygonal in longitudinal cross section having a top side 70 a front side 72 and a pair of bottom sides 74 76 which meet at an obtuse angle the bottom side 74 containing the light outlet aperture 64 the channel 62 is shown in fig2 and 3 as being non linear with an elbow 78 functioning to provide a bend in the fiber optic element 66 so as to direct the light beam as desired on the lateral work area adjacent and in axial alignment with the drive stem 26 in fig4 the switch element 20 as shown in fig2 is shown in greater detail in its 34 off 34 position the cap 30 has a pin 80 extending diametrically across the interior thereof the pin 80 engages a sleeve 82 in the plug 32 the bias spring 34 urges the cap stem 38 and.