Spanners are used tobridge the space between flatcars sothat vehicles can be driven forwardto their designated blockingpositions. Spanners are simple tofabricate and are built to take theheaviest vehicle being loaded. Figure 2.3 shows spanners ofdifferent capacities and a pair ofspanners placed between cars. The main objective of blockingand bracing an item is to insurethat it will be immobile duringtransit and arrive at itsdestination in good condition. Figure 2.2. Improvised Ramp.