Blades 53 55 are parallel to one another and are oriented at {HEAD ~ an angle} identical to {TAIL ~ the angle} of slots 50 52 
identical to
Blades 53 55 are parallel to one another and are oriented at { HEAD ~ an angle } identical to { TAIL ~ the angle } of slots 50 52
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH