For imperial units, fractional representation is more difficult in a digital format than in an analog format (while properly representing accuracy). There is a compromise between speed and accuracy displayed; it is easier to read in 1/16s than 1/64s. To help capture the best of both speed and accuracy, an "X" marker has been added to help show how close a measurement is to a given fractional unit. An X indicates right on the mark while arrows <> in either direction indicates the direction of travel to hit the mark. This feature is only present in fractional modes.