There are four main different faces that you may see on dial test indicators. Each one has a particular type of reading that it is ideal for. The continuous dial test indicator is the most standard type you might picture. On a continuous dial face the numbers go around the face and increase clockwise. These are used for direct reading. A balanced dial face for multiple revolutions has numbers increasing from the zero point in both directions and meeting in the middle at 50. These dial test indicators are used for reading the difference between a specific reference surface and your part. Continuous dial faces can also have a reverse reading where the numbers increase counter-clockwise along the dial. These are typically used for depth or bore gauge measurements. Finally, a dial test indicator could have a balanced dial face built for only one revolution. These are great for very precise readings of small differences.