Absolute Unit of Current

The Absolute Unit of Current in the CGS (centimeter, gram, second) system is defined as

The amount of current which when flowing through a wire shaped in the form of an arc with a radius of 1 cm exerts a force of 1 dyne on its center.

This definition provides the relationship between electrical and magnetic units.

The medium is assumed to be air or vacuum.  The permeability of air is assumed to be unity.