Brown & Sharpe tempered steel rules have a hooked end and four graduations with bulls-eye markings on 32nd and 64th graduations to measure workpieces in fractions of an inch. The hooked end ensures that the rule is aligned with the end of the workpiece or can slide out of the way when not required. Numbered graduations and bulls-eye markings on 32nd and 64th graduations speed reading and reduce counting errors. The ruler is constructed of 0.046″ thick tempered steel to provide durability.
Rules are devices used to measure distances, or to rule straight lines. Rules have markings at specified intervals (also called graduations), as opposed to straight edges, which lack graduations and are used solely to draw a straight line. Nearly all rules are straight edges, except for rounded rules used to measure circles and arcs of angles in geometry applications. Rules can vary from high-quality steel instruments used by machinists; to retractable rules (also called tape measures) used in carpentry and for home-use; to simple wooden or plastic rules used in primary and secondary schools.
Brown & Sharpe manufactures precision measuring equipment and metrology hand tools. The company, founded in 1833, is headquartered in North Kingstown, RI.