Shadakshari Lokeshvara is the four-armed emanation of the male deity Avalokiteshvara, the bodhisattva of compassion, known as Chenrezig in Tibet and as the female deity Kuan Yin in Japan.  Avalokitshvara (Lord who gazes down at the world with compassion) is ultimately an emanation of the Dhyani Buddha Amitabha.  

Shadakshari Lokeshvara means Six-Syllabled Lord of the World, which refers to the mantra OM MANI PADME HUM, Hail to the Jewel in the Lotus. That he is the Lord of the World is also indicated by the six syllables which refer to the six realms of the wheel of life, each of the syllables being the seed syllable for one of the realms, from which Avalokiteshvara delivers beings into enlightenment.  

Shadakshari is one of the 108 emanations of Avalokiteshvara.  In his upper right hand he holds a string of 108 beads, which represents the number of times that his mantra is recited.