M166.  Iron sukashi tsuba.  9 x 9.5 x .4 cm.  The nakago hitsu-ana measures .8 x 3 cm.  Huge tsuba with dense plate and subtle tekkotsu all over.  I think this is an abstract landscape.  I see a mountain with terraced fields, a hut beside a stream, and possibly a plow?  Nice tsuba whatever it is.  $75.