Koyo Alloy High Performance Radiator - R Series - MR2 MK3, MR-SKoyo Alloy High Performance Radiator R Series MR2 MK3, MR S 53mm Core R SERIES 53mm Core Thickness Koyo's "R" Series aluminium radiators feature an all aluminium core brazed to polished aluminium end tanks for a show quality finish. Koyo uses state of the art Nocolok Brazing Furnace to bond all of the radiator brackets, headers, tubes, and fins, creating high quality "indestructible" radiator. All aluminium end tanks are hand crafted using the latest