21 ECT ECT SYSTEM A B C D 1 2 3 3 1 4 2 1 2 3 4 5 7 8 10 11 2 4 1 3 5 6 7 13 20 21 22 23 24 E YELLOW F BLACK G H 3 1 2 3 1 2 10 15 1 2 2 12 22 23 6 I J K BLUE 1 2 7 8 9 8 3 4 L GRAY M BLACK N BLUE 1B 5 6 5 17 1F 1G 1L 1N 2 3 10 1 9 2B BLACK 3B BLUE 7A ORANGE 5 6 15 13 14