| 摘要 |
<p>The key ring consists of a ring with a pendant (1) which is sufficiently large to reduce the risk of losing it. The pendant can be made of metal and can have, on each face, a circular hollow disc (1a). This disc is by phosphorescent substance protected by a transparent plastic film (3). The pendant can be made in a translucent plastic with some particles of phosphorescent material included in the mass of the plastic.</p> |
