MIL-HDBK-1271, DEPARTMENT OF DEFENSE HANDBOOK SYMBOLS TO SUPPLEMENT THE TEXT OF INSTRUCTION PLATES FOR MILITARY VEHICLES. The purpose of this standard is to establish a uniform system of pictorial symbols to label equipment controls where symbolic representation is desired. 1.2 Scope. This standard specifies symbols to be shown on military vehicle instruction plates in addition to the text. Controls, indicators and tell-tales of a road vehicle are provided with symbols to ensure their identification and facilitate their utilization. This standard also indicates the colors of possible optical tell-tales which warn the driver of the operation or malfunctioning of the devices and equipment connected to the corresponding controls.