In a preferred embodiment described herein, {HEAD ~ the mirror} has {TAIL ~ a conventional, well known trapezoidal configuration} 
In a preferred embodiment described herein , { HEAD ~ the mirror } has { TAIL ~ a conventional , well known trapezoidal configuration }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL