The above photograph shows a half reform lip plate. The amount of build up on the blowing edge is significantly less than on a full reform lip plate. As a result there is no obvious ridge on the lip plate
The above is on a 9k Gold Headjoint by Trevor James.
The above photograph and notes are as accurate as my knowledge of the subject permits
If anything above is factually incorrect, or if anyone can usefully improve or add to the above notes then please feel free to email me at john@fluteweb.net