Millimeter, also known as millimeter (or millimeter), is a unit of length and rainfall, the English abbreviation mm. English abbreviation mm (or millimeter, also known as The unit of length is measurement About the feed rate of millimeters: 1mm = 0.1cm; 1mm = 0.1cm = 0.01dm = 0.001m = 0.000001km = 1 000m = 1 000 000nm