18" Cable Chain with 2" Extender One for you, one for your BFF! Each Pendant is .75" In Chinese philosophy, yin yang (yin-yang or yin yang, never yin and yang, because they flow into one another) describes how opposite or contrary forces are actually complementary, interconnected, and interdependent in the natural world, and how they give rise to each other as they interrelate to one another. Many tangible dualities (such as light and dark, fire and water, expanding and contracting) are thought of as physical manifestations of the duality symbolized by yin yang. This duality lies at the origins of many branches of classical Chinese science and philosophy, as well as being a primary guideline oftraditional Chinese medicine, and a central principle of different forms of Chinese martial arts and exercise, such as baguazhang,taijiquan (t'ai chi), and qigong (Chi Kung), as well as appearing in the pages of the I Ching. We sell quality items at reasonable prices!