Looks like a copper/brass cooler to me. Many cars I've seen have an aluminum radiator with an aluminum or plastic tanks. A fair amount do have brass/copper radiators though. Copper/brass radiators were used almost exclusively until the 1970s. The use of aluminum cores became quite common in the 1980's and well into the 90's. There seems to be a trend of moving back some to copper/brass coolers though. One of the main reasons that aluminum became common was its lightweight factor. Aluminum radiators were around 3X lighter than copper ones. Copper/brass coolers have come a long way since then, and are much more compact and effecient than before. In addition, copper/brass tends to be easier to work with and repair.