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|Defining the units used by other attributes' values on the same element.|
|Used on these elements|
|Tools for this tag|
- See also addr:unit=* for specifying sub-housenumber addressing.
|This is not an accepted tag, and indeed may be flawed. Please see the discussion page for more information.|
unit=km/m/miles/mph/... has been suggested for defining the units used by other attributes' values on the same element, based on the assumption that it may be better for data handling to have the unit separated out from the value of a key.