This specification covers the requirements for two types (Types 8.8 and 10.9) of compressible-washer-type direct tension indicators, in nominal diameter sizes M16 through M36, capable of indicating the achievement of a specified minimum bolt tension in a structural bolt and are intended for installation under either a bolt head or a hardened washer. Steel materials used in the manufacture of direct tension indicators shall be designed, processed, heat treated, and protectively coated as specified. The direct tension indicators shall conform to required chemical composition, compression load, outside diameter, number of protrusions, thickness values, inside diameter, and protrusion tangential diameter values.