I have a Yani alto with no engraving on it other than the serial number 11751950 and the Yani Y / harp logo and the number 5 to the left of word Japan. Thinking maybe it's an A-500 based on other opinions but key work seems to be slightly different than other 500's pics I've seen and serial doesnt seem to stack up by I am no expert. Thought perhaps someone here could help.