This tab contains two grids: one tracking information on structure type and material, the other tracking age and service. The codes in these fields correspond with the Federal Highway Administration's guide. The information tracked in the type and material grid includes material and design information, unit spans, number of approaches, and surface protection. The information tracked in the age and service grid includes year built, type of service, lanes, ADT (Average Daily Traffic), bypass/detour length, and year reconstructed. The special functions for main code and sub- code fields discussed above apply to this tab as well.