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...was what the conductor in the caboose might have thought when he saw these three zeroes on a hot box detector. Other conductors would use such descriptive phases as "three donuts and a twinkie" or that was the balance in their bank account when seeing this triple zero indicator. A triple zero would indicate that there were no defects. If the lighted number read something like 83, that would mean the problem was 83 axles ahead of the caboose. Just like cabooses on freight trains, these type of hot box detectors are a piece of railroading history. This particular scene was taken in Banff, Alberta Canada back in August, 1986.