Wikipedia
Shatkona
The Shatkona is a symbol used in Hindu yantra that represents the union of both the male and feminine form. More specifically it is supposed to represent Purusha (the supreme being), and Prakriti (mother nature, or causal matter). Often this is represented as Shiva / Shakti.
The Shatkona is a hexagram and is associated with the son of Siva-Sakthi, Lord Murugan.
Stylistically, it is almost identical to the Jewish Star of David and the Japanese Kagome crest.