The properties, dimensions, and weight per foot for steels can be found in the Manual of Steel Construction by the American Institute of Steel Construction. Commonly used shapes include the following, the wide-flange beam that is used for column, girders, and beams, designated with a "W", and has a weight of 30 lbs per foot; the American standard beam that is sometimes used as girders and beams, designated with an "T", and has a weight of 70 lbs per foot; the American standard channel that is used as beams and stair stringers, designated with an "C", and has a weight of 40 lbs per foot; structural tees that are used in steel trusses, designated with a "S", and has a weight of 29 lbs per foot; angles that are used as cross-bracings, lintels, ledgers, and connectors in the construction of steel trusses, designated with an "L", and has a weight of 12.8 lbs per foot; structural tubing that is used as columns and cross-bracing in the construction of steel trusses, designated by the length of its longest cross-sectional axis, the length of the other axis, and the wall thickness of the tubing (as an example, a tubing with dimensions of