serially connected to the first portion 56 at point 66 this section is shaped to extend partially around the inner periphery of the tubular member 48 this element serves as a positioning portion the third portion 60 is connected to the second portion 58 at point 68 it is shaped to extend across the circular cross section of the tubular member 48 from the point 68 to a fourth point 70 located on the inner periphery of the tubular member 48 the third portion 60 is spaced from the first portion by a distance slightly less than the thickness of the printed circuit board 52 accordingly this portion serves in cooperation with element 56 as a gripping portion the fourth portion 62 is serially connected to the third portion 60 at point 70 it is shaped to extend partially around the inner periphery of the tubular member 48 from the point 70 to a fifth point 72 located on the inner periphery of the tubular member 48 the fourth portion 62 is also made of a resilient material and has a radius of curvature which is slightly greater than the inner radius of the tubular member 48 accordingly this member functions as a.