Golden Mean Calipers - 4 armsEye Design's Acrylic Golden Mean Calipers The Golden Mean (also called The Golden Ratio, Phi, The Divine Proportion) is a simple ratio (1 to 1. 618) that is considered aesthetically beautiful, and which has been used in art and architecture for thousands of years. They open close a bit like a divider, the ratio of the distance between first, third and fourth points are always The Golden Mean : 1. 618 to 1 Lightweight acrylic Golden Mean Calipers are