a heat receiving portion to couple to a heat generating unit, {TAIL ~ the heat receiving portion} has a recess corresponding to {HEAD ~ the heat generating unit} 
a heat receiving portion to couple to a heat generating unit , { TAIL ~ the heat receiving portion } has a recess corresponding to { HEAD ~ the heat generating unit }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD