Fist
A stranger told me that a doctor told him that the size of your fist is roughly the size of your heart:
"Heart" = 24 (Septenary) ---> 2+4= 6
"Fist" = 24 (Septenary) ---> 2+4= 6
"Fist" = 18 (Full Reduction) ---> 1+8= 9
"Hand" = 18 (Full Reduction) ---> 1+8= 9