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