K220.  Kinko tsuba (may be Ko-Kinko; what do I know) of shakudo or some other patinated alloy of copper.  6.2 x 6.6 x .4 cm at the raised rim.  The nakago hitsu-ana is .7 x 2.7 cm.  A business partner & I recently purchased a wooden box containing 108 tsuba that had been discovered along the back wall of a kura (storehouse) in Japan, undisturbed for 100 years.  This is one of the 108 (more to come).  Condition of this one is excellent; it is quite nice.  $165.