Since the pin is symmetrical, its orientation relative to the circuit board is unimportant, which facilitates {HEAD ~ automatic insertion} of {TAIL ~ the pin} into the board 
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Since the pin is symmetrical , its orientation relative to the circuit board is unimportant , which facilitates { HEAD ~ automatic insertion } of { TAIL ~ the pin } into the board
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH