Equidistant Conic 

Release 9.2
Last modified August 3, 2007 
Print all topics in : "Supported map projections" 
This conic projection can be based on one or two standard parallels. As its name implies, all circular parallels are spaced evenly along the meridians. This is true whether one or two parallels are used as the standards.
Cone is tangential if one standard parallel is specified and secant if two standard parallels are specified. Graticules are evenly spaced. Meridian spacing is equal, as is the space between each of the concentric arcs that describe the lines of latitude. The poles are represented as arcs rather than points.
If the pole is given as the single standard parallel, the cone becomes a plane and the resulting projection is the same as a polar Azimuthal Equidistant.
Learn more about the Azimuthal Equidistant projection
If two standard parallels are placed symmetrically north and south of the equator, the resulting projection is the same as the Equirectangular projection. In this case, you must use the Equirectangular projection. Use the Equirectangular projection if the standard parallel is the equator.
Learn more about the Equirectangular projection
Depends on the number of standard parallels.
Tangential projections (Type 1)—one line, indicated by the standard parallel.
Secant projections (Type 2)—two lines, specified as the first and second standard parallels.
All meridians.
Range in latitude should be limited to 30°.
Regional mapping of midlatitude areas with a predominantly east–west extent.
Common for atlas maps of small countries.
Used by the former Soviet Union for mapping the entire country.