The term SOME DASH LENGTHS refers to two different types of uniform measurements, ENS (3 letters) and EMS (3 letters). ENS stands for 'even number series' and is a system of uniform measurements used in the United States Navy. EMS stands for 'European metric system' and is a system of uniform measurements used in Europe. Both systems are used to measure the length of a garment, such as a shirt or pants, from the shoulder to the hem.