In the preferred embodiment, the oblique angle formed by these end surfaces is 15° from {TAIL ~ a plane} positioned normal or perpendicular to {HEAD ~ these axes} 
In the preferred embodiment , the oblique angle formed by these end surfaces is 15 ° from { TAIL ~ a plane } positioned normal or perpendicular to { HEAD ~ these axes }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD