| 摘要 |
<p>The cover has marks (31, 32) provided or designed such that a plug-in module (30) with marks is insertable in the cover or between the cover and a finger-board of necks. The cover is partly transparent and/or contains an opening through which the marks are visible. The cover rests on the finger-board when the finger-board is attached at the necks. Fixing devices i.e. slide or snap fasteners, are provided and allow fixation at the necks. The marks indicate grasps pertinent to defined notes. Notes description is included in Braille.</p> |
