{HEAD ~ The knob} 80 has {TAIL ~ an annular portion} 82 arranged for frictional engagement with the exterior surfaces of the rear wall 66 on each side of the slot 76 
{ HEAD ~ The knob } 80 has { TAIL ~ an annular portion } 82 arranged for frictional engagement with the exterior surfaces of the rear wall 66 on each side of the slot 76
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH