In Chinese Philosophy, the concept of Yin Yang is used to describe how polar or seemingly contrary forces are interconnected and interdependent in the natural world, and how they give rise to each other in turn. This acrylic plug depict the symbol on both sides, one side is rimmed by your choice of 5 colors, and on 8g through 2g, the other side is the symbol alone with no color around the edge. 0g and 00g have color around the edge on both sides. This plug is available in 6 gauges, from 8g to 00g. All gauges have a 5/16" wearable length from the back of the front flare to the included o-ring.