Tonic A / Key of E. The tonic of the bansuri is the note sounded when 3 finger holes are closed. 6 holes closed determines the key. The same flute may be referred to by either its tonic or key. A perfect compliment to any flute collection! The precisely crafted low E flute is in tune, and ready to play! Natural bamboo with black nylon cord end wraps. $58.00