Unit: metre
Data source: EPSG
Information source: US Army Map Service Technical Manual No. 7; 1943.
Revision date: 2013-01-17
Remarks: Original definition a=20926062 and b=20855121 (British) feet. Uses Clarke's 1865 inch-metre ratio of 39.370432 to obtain metres. (Metric value then converted to US survey feet for use in the US and international feet for use in Cayman Islands).