This item is a sterling silver pendant necklace with an 18" chain.  The pendant represents: 

The Buddha: 

'Awakened One,' suggesting that his enlightenment was a 'waking up' to the world as it really is, free from delusion and ignorance.

The Dharma:

The essential teachings of the Buddha.

The Sangha:

The monastic community founded by the Buddha, which is highly revered as they make the Buddha's teachings the exclusive focus of their lives.