a/c tubes/radiators

one radiator i had it had ali wrapped around it and a single copper tube what is it called? it did not have loops on the ends like most of the ones i have seen are they rare? the tubes inside a a/c radiator i know they are num 1 without solder but is there such a thing as bare bright tubes or does it only count for wire? could not find google pic of this type of radiator=(

if the metals are aluminum and copper it is considered aluminum copper radiator. no such thing as bare bright tubes