This symbol is best known as the Valknut, or knot of the slain, although it is sometimes called Hrungnir's heart, after the legendary giant of the Eddas.
The original meaning and function of the valknut is not wholly clear. The Valknut is associated with the God Odin, perhaps symbolizing the knots of the rope he used to suspend himself for nine days and nine nights from Yggdrasil, the world tree, and was pierced with his own spear, Gungnir, in order to discover wisdom that would give him power over the nine worlds. Odin gained the power to bind and unbind the mind, so that men became helpless in battle, and he could also loosen the tensions of fear and strain by his gifts of battle-madness, intoxication, and inspiration.
The Valknut is often found on Scandinavian stone carvings as a funerary motif, where it probably signified the afterlife, and Odin's power over death.
This pendant is 1 inch (35mm) wide by 1 inch (35mm) tall. It is available in bronze or sterling silver, and comes with an 18 inch long gold or silver tone steel necklace.