Double zebra cowls. CN's first four SD60F's (CN 5500-5503) are alternately known as SD50AF's and were numbered 9900-9903 from 1985 to 1988. They differ from the rest of the SD60F's by having high mounted numberboards, as did their SD50F predecessors (all now off of CN's roster). Here SD50AF CN 5502 leads a GE cowl (CN 2402) through Dorval on a brutally frigid morning.
