b) a number with three figures indicating the unit or unit component. c) a figure indicating the nature of the section. - figures O O O indicate the characteristics of the vehicle - figures O O indicate the characteristics of the unit - figure 0 indicate checks and adjustment - figures 1 4 7 indicate the removal and fitting - figures 2 5 8 indicate stripping down and reassembly - figures 3 6 9 indicate reconditioning