The appearance of this Fudō is based on the Tendai Buddhist iconography known as “The Nineteen Visual Characteristics of Fudō” (J. Fudō jūkyūkan yō). An inscription engraved on the back of the statue reveals that the monks Kan’yū and Monken (dates unknown), who appear to have been its sponsors, had it produced in 1269 (Bun’ei 6). The arms were cast separately. Attaching them to the body with tenons (J. hozo), as they are here, is a technique common to gilt-bronze Buddhas from the Kamakura period(1185–1333).  
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It was said that the left hand might have held a lasso (kensaku) and the right hand might have grasped a sword. The head was decorated with curly hair, the left fang was exposed downward and the right fang was upturned. The squinted left eye was downcast and the right eye was turned. The inscription on the backside indicates the date of fabrication and the names of priests who were probably principal wishers.
 
Shigeki Iwata 
Masterworks from the Nara Buddhist Sculpture Hall at the Nara National Museum. Nara National Museum, 2010, p.137, no.162.