Non-SI units mentioned in the SI

Some units are deeply embedded in history and culture, and their use has not been entirely replaced by their SI alternatives.

Most societies have used the solar day and its non-decimal subdivisions as a basis of time and, unlike the foot or the pound, these were the same regardless of where they were being measured.

[2] Most of these, in order to be converted to the corresponding SI unit, require conversion factors that are not powers of ten.

The following table lists units that are effectively defined in sidenotes and footnotes in the 9th SI brochure.

Units that are mentioned without a definition or that occur in historical material recorded in the appendices are not included.

While not an SI-unit, the litre may be used with SI units. It is equivalent to ( 10 cm ) 3 = ( 1 dm ) 3 = 10 −3 m 3 .