Flex-A-Lite makes radiators for CJs, YJs, and TJs in addition to the new XJ radiator. All its aluminum radiators feature the same finned tanks. On the open-top Jeep line, the tanks are often used to bolt shrouds or overflows on to the tank itself rather than poking through the core with Christmas trees. In all versions there are the external fins you can see as well as internal fins which also help to grab heat. We got some cutaways of the extrusion so you can see inside the tanks. On the left is the open-top Jeep tank and on the right is the XJ tank.