{HEAD ~ An upper case} having an insulated inner surface including a sidewall structure complementary to the lower case sidewall structure forms {TAIL ~ a lid} for the channel and is insulated from the lower case 
forms
{ HEAD ~ An upper case } having an insulated inner surface including a sidewall structure complementary to the lower case sidewall structure forms { TAIL ~ a lid } for the channel and is insulated from the lower case
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH