Together, the inner surface 508 and {HEAD ~ top plate} 512 form a passage 516 that extends through the entire length of {TAIL ~ the interpole wedge} 502 
Together , the inner surface 508 and { HEAD ~ top plate } 512 form a passage 516 that extends through the entire length of { TAIL ~ the interpole wedge } 502
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH