The measure chosen for the basic unit (equivalent to a tenth of a mètre, measuring 1 dm) was the mão travessa, defined as a 10-millionth part of a quarter-meridian, according to the original definition of the reference unit of the metric system.

Multiples of the mão travessa:

• Vara = 10 mãos travessas (1 metro);
• Milha = 10 000 mãos travessas (1 km);

Submultiples of the mão travessa:

• Décimo = 0,1 mão travessa (1 cm);
• Centésimo = 0,01 mão travessa (1 mm).