It is a symbol of self-sovereignty, the authority of governance and the power of rule. The gada is the main weapon of the
Hindu god Hanuman and Known for his strength.
The mace represent concentrated prana (life). It is considered a sign of bravery, immense physical strength, virility and radiance like sun.
http://shree-hanuman.blogspot.in/2013/08/significance-of-hanuman-gada-mace.html